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FAQs on the Molly Infectious Disease:
(Virus, Bacterial, Fungal)


FAQs on Molly Disease:
FAQs on Molly Disease by Category: Environmental, Nutritional (e.g. HLLE), SocialParasitic (Ich, Velvet...), Genetic, Treatments
FAQs on Molly Reproduction/Breeding
Molly Reproduction 1, Molly Reproduction 2, Molly Reproduction 3,

Almost all infectious diseases are instigated via environmental stress. THESE stressors need to be addressed ahead of any treatment regimen.

Mollies. Again.       2/14/17
Hi, Neale - long time, no questions! Hope you had a good holiday and that the new year is treating you well.
<All good; thanks for asking.>
This morning we noticed that we have a silver sailfin Molly that's just lying on the bottom or swimming lethargically, using only her pectoral fins. She doesn't use her tail to swim at all. Her tailfin seems kind of shredded lengthwise, but doesn't look bitten. She had gotten big, we thought she was pregnant (assuming one of the 7 young mollies is a male), but she seems slimmer now. We have seen any fry in the tank, though we didn't really look (I'm only just now thinking of it).
We have another Molly, a creamsicle, that is starting to shimmy.
<Typically a stress reaction, though quite what the stress factor might be isn't always obvious. Mollies are easily stressed by chilling, nitrate, and the wrong water chemistry, though like all fish, non-zero ammonia and nitrite are issues too.>

The numbers are good in the tank - ammonia and nitrite are 0, nitrate is 20.
<Sounds good, but no mention of water chemistry here. Will (re-) state the importance of carbonate hardness to Mollies; alkaline water with a basic pH is an essential, especially if salt is not added to the water. Tanks will acidify between water changes, and this causes problems for Mollies in particular. Simply doing a substantial water change or three will often help Mollies return to their normal happy selves. Failing that, adjusting water chemistry slightly, by the addition of sodium bicarbonate -- one teaspoon per 40 litres/10 US gallons is a good start. Easiest approach here
is estimate size of tank, make up the correct solution for that volume, and then add to the tank in small amounts across a few days, giving time for the fish to adapt. Alternatively, just add the right amount of a given bucket of water (so might easily be a quarter teaspoon for a 2.5 gallon bucket) and do your water changes as per normal. I do prefer to keep Mollies in low-end brackish conditions, but understand that isn't an option in all cases. Read up on the pros/cons of this, and act accordingly. Would also check the heater, and maybe turn it up a notch, Mollies preferring quite balmy conditions compared with standard community tank fare; 28C/82F is not out of line for the bigger, sailfin varieties in particular.>
Tell me what I forgot to tell you and I'll provide the info, but this is about it, that I can see. As always, thanks so much for your help!
<Most welcome.>
Tom & Maria
<Cheers, Neale.>

re: Mollies. Again.     2/14/17
The water is relatively hard, and it goes in at around pH 7.8, then the tank adjusts up to 8.0 to 8.2 with the bubble stone and stays there. Maria changes the water weekly at a 25% change. The numbers have all been stable NH3/4, nitrate, nitrite, pH, etc, for months.
She's still hanging in there, but in a head up position. Could this be bacterial?
<Yes, but environment is what you look at first.
If you're content that the tank is good, then sure, treat with an antibiotic. Livebearers are sometimes given to strange "wasting" diseases after a certain length of time -- whether old age, dietary shortcomings (do bear in mind they're herbivores in the wild), social stress, or inbreeding is hard to say. But colonies of livebearers frequently do well for years, but individual fish may have substantially shorter lifespans than you might expect.>
Why would the tail separate into lengthwise strips?
<Typically physical damage, such as fighting. Do bear in mind Mollies are prone to fighting. You could medicate as per Finrot, but keep a close eye on the fish for evidence of squabbling. Cheers, Neale.>

Mollies, hlth.  - 4/17/12
Danielle here again.
<Hello Danielle,>
I have 5 adult balloon mollies- an orange female and she's the one I've had the most and my favorite, 2 creamsicle females, a female with a silver top and white bottom, and a creamsicle male. 8 days ago I brought home the two newest ones. 1 creamsicle male and 1 creamsicle female. I bought them at a place I shouldn't have for the first time, I regret it very much, and that will be the last time. I got them at Petco. I don't have a quarantine tank unfortunately- and never needed one before I went here because the place I always go is so great. The place I usually go to is called That Fish Place That Pet Place. They take unbelievably great care of their fish. All of their staff are either biologists, seasoned hobbyists, or some other sort of trained professional.
<Real good.>
Most of the time they quarantine them themselves. Every time I've seen them restock they always have tags reading under observation for such and such amount of time. I have NEVER had a problem and now my whole tank is infected with something. The one that has it the worst is one of the two I just brought home.
There are two spots on his gills, well the outside of them. They're white and I can't tell if they're his scales that are irritated or cottony looking stuff.
They are in the same spot one on each side and only in that one place that he rubs. There's nothing on the rest of the body. Unfortunately I can't get a picture of him or any of them, they're too squirmy. Plus they're flashing off the bubbler tubing, filter, and rounded decorations. I read on here that salt and higher temperature will work if I don't want to use medicine.
I started that yesterday. but I also noticed that that post was from 2003.
So I hope that's still true/helpful.
They always had brackish water with marine salt in(instant ocean to be specific) - .5oz/1 gal. So I upped it to 1oz/1gal. and the temp is up to 84.
<This should help a good deal. Do also treat with an antifungal, and ideally one that knocks off Finrot too -- e.g., Seachem Paraguard.>
But I'm still really nervous. The other fish don't have the white spots on their gills but they're all rubbing/flashing off their gills like the male.
Except for 2.
The one is the fish I've had the longest and another is a younger one. But I figured if everyone else has it they're just not showing signs yet.
I thought since I had the salt in, that I wouldn't have much to worry about and I didn't until now. I do 30-50% water changes about 2 times a week. I tested the PH today and it was at a 7.6 like usual. I haven't gotten a nitrite/nitrate test yet but I have it ordered.
<Ah, would check this. In brackish water, Mollies are normally bullet-proof, but Balloon Mollies are obviously very inbred, and the result is less hardiness compared to the "real McCoy".>
I do use water conditioner though. Every time I fill, replenish, or clean.
I even add it if I noticed babies were dropped or anything dead. With the frequent water changes I would think there shouldn't be that much of a problem.
<I agree. And normally, Mollies are fine in mature brackish aquaria.>
For over 3 moths I've had it set up and until now its been perfect. Its really frustrating when you spend so much time taking care of it, watching it grow, and money and then have it all go down the drain. I also have a tank for when they have babies. But that tank is fine since I didn't put any of the sick ones in with them. I did try tetra life guard for two days but that just seemed to make it worse and was a waste of money.
<Would tend to agree. Many of these inexpensive, cure-all medications aren't that reliable. Okay as preventatives perhaps, when you have a fish that's got damaged but otherwise seems just fine. But not something I'd reach for when fish are visibly sick.>
Plus I don't even know what the issue is so I was hoping you could tell me.
They don't clamp their fins, swim around lively, eat A LOT and their colors are still beautiful. I hate to see them suffer. There are a few babies in with them and I was going to move them to the baby tank but I didn't want to infect the others- there's 135- 3 different ages and they won't stop popping them out!!!!
<A lot of fish!>
I never had a male until 8 days ago but the tank at the store wasn't lacking in the males. I know they can store sperm for a while but gosh how many batches can they have!?
<Many; some relatives of the Molly have produced six batches from one mating. Do bear in mind juvenile males as young as 2 months can be fertile.>
My favorite has had 3 and looks like she will have more, my black one has had 2, and one of the creamsicles( the one from That Fish Place) has had 1 but there were only 7 from her. I've noticed after each batch the number grows as they grow/get older. The biggest batch I've had so far is 70 and that was from my black one. But of course I have lost a few from natural dyeing off and getting sucked into the filter but not many suffer that fate at max 5- I have saved a few from it. 
The black one is in the baby tank. She's rude, mean, temperamental, and tortures the other adults but leaves the babies alone.
<Do bear in mind Mollies are very hierarchical and far from peaceful, and a healthy big Black Molly will often bully weaker examples of delicate strains like Balloon Mollies.>
I don't know what her deal is but she's quite happy in the baby tank.
<Fair enough.>
She's been that way since I brought her home so it's nothing new. Im trying to find them homes and our LFS is willing to take some when they get big enough.
I don't know if it makes a difference but there no gravel or substrate in the tanks, I don't like it and I feel like stuff just gets stuck in it. I do have decorations and plenty of hiding spots.
Sending you pictures that I should have had with my other email. One should be of the tank, one should be of a creamsicle fish the one I got at Petco, and the other should be of the male fish with a circle around where the spot is. This is the tank as of right this moment. The creamsicle actually didn't have that color at all when I got her from Petco. She barely had any color at all and now she's a beautiful gold. I don't know if its because she was unhealthy at the store, naturally turned, the food I'm giving them(all of the fish's color have gotten more vivid and beautiful since I bought them) or what but she looks great. Then there's the male with the spot on his cheek. It's exactly the same on the other side too but I couldn't get the other side.
<I'd use a good, reliable antifungal, anti-Finrot medication together with the salt/heat you're already using. Seawater dips for 20 minutes at a time would be useful for the specimens with obvious damage/tufts. Seawater is 35 grammes salt mix/litre, and you only need to make up a litre at a time, so it's a cheap way to blitz the pathogen. Mollies should take 20 minutes without problems, but if it keels over before then, return it to the brackish water. Cheers, Neale.>

Re: Mollies   - 4/18/12
Will API fungus cure work? that's the only thing I can find around here that seems to get good reviews. What you mentioned they don't have around here.
<Should deal with Fungus. Has no effect against Finrot. So wouldn't be my first choice. Do hunt online if possible for a good, reliable medication that treats both Finrot and Fungus at the same time (though not a tea-tree oil type product like Melafix that *says* it treats both but usually does neither). Waiting a day or two delivery shouldn't kill the fish, especially
if you do the seawater dips daily. Cheers, Neale.> 

Re: Mollies    4/18/12
Thanks so much for all your help. You guys are really awesome and your website is great.
Re: Mollies    4/18/12
One more question. Can I put the old filter cartridge back in or is it a better idea just to use a new one?
<Carbon and zeolite ("ammonia remover") need to be replaced regularly anyway, every 2-3 weeks. But biological media (sponges, ceramic noodles) should be rinsed (ideally in aquarium water) and reused as often as practical. If you must replace biological filter media, replace no more than 50% within a 6-week period. Cheers, Neale.>

Re: Mollies    4/20/12
So I've noticed slight discoloration on the creamsicle Balloon Mollies on the top of their heads. It looks like dry skin and then its slightly dark under. It doesn't look too intense. Will it clear up as soon as I clean the tank and treatment is over? I saw in the post: "Re Balloon Molly with "cracked dry spot" and discoloration on top of her head. Please HELP!
that it could be from medicating. It looks just like that except not nearly as bad. I'm just hoping its nothing to worry about once treatment is done.
They're all still lively and eating well(little pigs actually). I have been doing the 20 minute salt dips like you suggested. They seem a lot livelier after I do the dips.
<Mollies like seawater!>
The flashing seems to have calmed down a lot. I have Seachem's Paraguard ordered just incase this does not clear up with API fungus cure. I really don't like this whole medicating thing. No filtering, no water changes, its cloudy but I don't want to ruin the purpose of the medication.
<Don't understand this. Any hospital tank needs a filter, either biological or else zeolite (ammonia remover) replaced on a regular basis.
Alternatively, treat in the main aquarium. If the fish are dumped in an aquarium without a filter, they'll be stressed by the ammonia, and no amount of medication will help them.>
I do have oxygen circulating and the filter is on just no carbon cartridge.
Is there anything I can do to keep it clean yet not ruin the whole purpose of medication? I read on Seachem's website about the Paraguard and it says that you don't need to take out your filtration. Is that true? Nitrate and Nitrite test should be here today - I tracked the package and it says out for delivery. And just to make sure I have it right - everything should be at 0? Except the PH of course.
<Ammonia and nitrite need to be zero. In brackish water, nitrate level isn't crucial, but certainly below 40 mg/l, and ideally below 20 mg/l.>
Thanks so much,
<The discolouration seen on Mollies is quite common, as it is with Black Moor Goldfish, and I suspect for the same sorts of reasons, excess mucous production, perhaps couples with patches of dead skin and/or skin parasites (e.g., Slime Disease/Costia). Generally clears up fine if treated for whatever ails them. Cheers, Neale.>
Re: Mollies
It says to take out the carbon filter. What do I do to keep the ammonia down? or should I just ignore taking out the filter
<Carbon has nothing to do with ammonia. So yes, you always remove carbon when medicating (except if you use salt or Epsom salt, in which case carbon doesn't have an impact either way). Ammonia is removed through biological filtration (i.e., sponges and ceramic noodles in use four 6+ weeks to become mature) or zeolite ("ammonia remover", which needs to be replaced every few days, as per the manufacturer's instructions or when you start detecting non-zero ammonia levels). Few medicines effect biological filter bacteria, but some do; refer to the manufacturer's instructions on this.
Cheers, Neale.>
Re: Mollies

Here's what the directions exactly say: For best results remove activated carbon or filter cartridge from filter and continue aeration.
<Yes: they are talking about carbon. Not biological filtration. You leave biological filtration _in situ_.>
For each 10 gal of water empty one packet directly into aquarium. Repeat does after 48 hours. Wait another 48 hours and then change 25% of the aquarium water and add fresh activated carbon or replace filter cartridge. Note this medication will discolor water and may stain aquarium sealant and ornaments. Use API BIO CHEM ZORB or activated carbon 48 hours after final treatment to remove color from water.
<Pointless unless the medicine is toxic to specific livestock, such as shrimps, but feel free to spend your money this way if you want…>
This package treats up to 100 gal. Two doses required for full course of treatment.
I was really confused by this because I know ammonia and all that other stuff is terrible. So what do I do?
Thanks, Danielle
<Cheers, Neale.>
Re: Mollies    4/20/12

Got my kit and my Nitrates if we count for fw: 10 or sw:20 and nitrites are 0
<Sounds fine. Time for less chatting Danielle and more reading! Do see the WWM articles re:, and then apply that knowledge yourself. Cheers, Neale.>

Molly trouble   4/19/09
Hello to the crew at WWM!
I have looked throughout your website at possible causes that could be contributing to the illness that one of my mollies, Bass, seems to have contracted. My fiance and I jumped into the aquaria hobby about 18 months ago and haven't looked back! Since mollies were the fish we had the best luck with, we kept them. As they grew up and bred (and bred and bred and bred), we just kept increasing their tank size. The majority of our mollies now live in a 125 gallon, 6' long tank. Temp is 80 degrees Fahrenheit; ammonia is 0; nitrite is 0; nitrate is 40 (water change is tomorrow). They get dechlorinator and a bit of non-iodized salt, but that's it.
<Would up the salt, and rather than using cooking salt, switch to marine salt mix. Besides raising the salinity, marine salt mix dramatically improves the pH and hardness levels. I'd recommend 6-9 grammes per litre, the lower end if you have plants in the tank. Check your other fish are salt-tolerant before raising the salinity. Almost all general problems with Mollies just don't happen when they're kept in brackish -- rather than freshwater -- conditions. Your nitrate level for example is too high for Mollies, but the use of brackish water will far reduces the toxicity effect.>
About six months ago, we purchased a female molly from our LFS and we decided to name her Bass (we name most of our fish for identification purposes). Last weekend, around April 11, we noticed that she was
whirling. We immediately prepped our 10 gallon quarantine tank and used tank water from the 125 gallon tank and placed her into there with some Formalin and Epsom salts to treat what was suspected to be a swim bladder issue. We also stopped feeding her for three days, then started feeding her shelled peas only at one pea every other day because it takes a while for her to eat a whole one. She started swimming fine on Thursday, April 16, so we put her back home into the 125 gallon tank. Bass then started whirling again, so we put her back into quarantine. Of course, now she is swimming fine, and we are still feeding her peas and regular fish food on a pattern basis. I joke that I think she is faking. Other than whirling and swimming as if she is drunk, she acts just fine.
<Rocking, listlessness, and "treading water" in Mollies is commonly put down to something called the Shimmies, a catch-all name for something caused by a potential variety of things including poor water quality and certain bacterial infections (particularly Columnaris). Columnaris, also called Mouth Fungus, is bacterial infection common among Mollies and often revealed by white-grey patches on the face and body.>
Are there any suggestions as to what could be the cause of this behavior/illness?
Thank you very much!
<Would amend water chemistry as noted, and if you suspect Columnaris, treat accordingly. Cheers, Neale.>
Re: Molly trouble 4/19/09

Thank you for your quick and thorough reply!
<Happy to help.>
After I received the message in my inbox, I feel I may have needed to include a few more details than I did previously. The 125 gallon is home to only mollies of various ages, backgrounds, and types. It is sparsely planted at the moment because the light necessary for some better plants is expensive. We have already set aside funds for it and will be purchasing the new light at the end of the month, however. The plants will definitely help with the nitrate issue.
<OK. Well, since you're keeping Mollies, raising the salinity to SG 1.003 is a no-brainer. Any plants tolerant of salt will accept this salinity, provided they're otherwise happy. I have a list of salt-tolerant plants on my Brackish FAQ, here:
We used to use Instant Ocean (16 teaspoons for the tank in addition to 16 teaspoons of non-iodized salt) in the molly tank when we did water changes.
The problem was that the Instant Ocean stressed them out somewhat.
<Can't think why. If it's safe for seahorses and corals, better believe it's safe for Mollies!>
Our next step is going to be to find a way to get it set up on a drip system using an empty water jug, aquarium tubing, and a flow regulator (this is coming soon) so that we don't have to just dump the Instant Ocean mixture into the tank all at once.
<Mollies can be acclimated between freshwater and seawater within an hour.
Have done this many, many times. Certainly true for Sailfin and Black Mollies, might not be the case for the more inbred mutant forms like Balloon Mollies, but I don't keep them. Wild Mollies at least will tolerate
any salinity you throw at them. But, and it's a bit but, your filter bacteria may need to adjust to dramatic changes in salinity. From 1.000 to 1.003 shouldn't cause problems, but bigger changes might. Do always use a hydrometer to check the specific gravity; don't rely on teaspoons or such!
A basic floating glass hydrometer costs $5.>
When we were using Instant Ocean, however, we lost several mollies within a few weeks of each other.
<Just don't believe these things are connected, unless the Instant Ocean was somehow contaminated.>
They were in the category I call the "teens" -- older than fry, not quite adult.
<Not an issue. Mollies will breed -- readily -- in seawater.>
The symptoms they began to exhibit right after the addition of the Instant Ocean product were crooked spine and whirling.
<Doesn't sound like a salinity issue; sounds more like a sudden change in pH, exposure to toxins, or something like that.>
Those fish were immediately euthanized after the crooked spine was noticed (I will not prolong the suffering of any animal, no matter how attached I am to him/her/it).
Now we have Bass, who is fine in quarantine but starts moving around listlessly and whirling once she is placed into general population. Does this still sound like a myxosporea/nitrate issue?
<Myxosporea is not common in tropical fish because the parasite has a complex life cycle that requires intermediate hosts. So unless these Mollies have been kept in a pond, I can't see how Myxosporea enter into the discussion. As for nitrate, this is an Achilles' heel for Mollies, but it's difficult to pin down the "toxic level" accurately. They do seem to be nitrate sensitive compared to other livebearers, so by analogy to other
nitrate sensitive fish, levels above 20 mg/l probably make them more prone to sickness. But beyond that, it's hard to say.>
If so, I will gladly find some copper sulfate at our LFS later today.
<Apropos to what? Copper sulphate isn't much used these days because it's pretty toxic, though concentrations of 0.15-0.3 mg/l can be used for up to 4 weeks to treat external parasites and flukes. Won't do much for fungus, Finrot, etc.>
Thank you very much again!
<Cheers, Neale.>

Mollies with Columnaris and Ich -- 03/22/09
Hello Crew,
<Hello Carla,>
I'm in a bit of a quandary. I purchased three mollies the day before yesterday, and placed them in my cycled 10 gallon quarantine tank (pH: 8.1, ammonia: 0, nitrites: 0, nitrates: 0 -- I had a bunch of extra cuttings so the tank is stuffed with live plants).
<Mollies don't do well in small tanks. They're very sensitive to nitrate as well as ammonia/nitrite, and in small tanks it is very difficult to keep them healthy for long. Minimum tank size for small Mollies (Shortfin mollies, black mollies, balloon mollies) is 20+ gallons, while large Mollies (Sailfin mollies, liberty mollies) is over 30 gallons.>
Unfortunately yesterday I observed that one of the mollies had what we used to call cotton mouth or mouth fungus.
<Very common with Mollies, especially when kept in freshwater conditions.>
I understand, from researching your site, that this is likely Columnaris (bacterial).
<Indeed. You will need a suitable antibiotic or antibacterial (as opposed to a make-believe solution such as tea-tree oil or salt.>
Today I also observed two Ich spots (sure glad I quarantined). I was going to go the salt + heat route, but I learned (also from researching your site), that Columnaris grows faster with higher heat.
<Your options are limited here, but in this case, I'd raise the salinity to deal with the Ick, and treat with an antibiotic/antibacterial at the same time. Since Mollies are best kept at SG 1.003, I'd recommend 6 grammes of marine salt mix per litre of water. There's not much point trying to keep Mollies in a freshwater aquarium because they rarely (seemingly, less than 50% of the time) do well. You're also fighting with one hand behind your back because the tank is so small, so a difficult job is being made twice as hard.>
My questions are: Should I raise the heat, and how I can treat both the Columnaris and Ich concurrently? Also, should I remove my plants?
<Plants will not be affected by antibiotics or antibacterials used correctly, and a salinity of SG 1.003 is fine for hardy, salt-tolerant plants.>
Thanks very much for your help and your wonderful website.
<Cheers, Neale.>
Re: Mollies with Columnaris and Ich   3/23/09

Thanks very much for your help. The Mollies are currently in a ten gallon tank because they are in quarantine (their permanent home will be a 40-gallon heavily-planted breeder tank).
<Ah, that makes sense. A 40-gallon system will be perfect.>
The water parameters of that tank are:
Ammonia: 0
Nitrite: 0
Nitrate: 0
pH: 8.2
Carbonate hardness: approximately 200 mg/L CaCO3
<That's 200/17.8 = 11.2 degrees KH. That's extremely high, and while perfect for Mbuna or Central American livebearers, a lot of other fish will find that a bit on the hard side for their tastes. Do be aware when choosing fish and plants.>
Their tankmates will be Wrestling Halfbeaks, Scarlet Badis, White Clouds, and Threadfin Rainbows.
<Halfbeaks will thrive, the others should tolerate, but may not show optimal colours or longevity.>
I was hoping the Mollies would do well without salt because of the high pH and hardness, and I wasn't sure (aside from the Halfbeaks) whether the plants and other residents would appreciate the salt.
<Plants that tolerate hard water generally do well in slightly brackish water too; species such as Vallisneria, Hygrophila, Java ferns, hardy Crypts, etc. If you have plants that need soft water, chances are they
aren't going to thrive a this level of carbonate hardness either, so it's a moot point. As for the fish: Halfbeaks tolerate salt well, but the others are truly freshwater fish.>
But I will add salt and remove some of the other residents and non-salt tolerant plants if necessary.
<Would be my recommendation. Mollies deserve a tank of their own: they're spectacular fish, and wonderful pets. But they are finicky in freshwater systems. They need perfect water quality. You might decide to medicate them in the quarantine tank, and when they're healthy again, try them out in a plain freshwater tank. With luck, you'll be okay. But if you find you're constantly having to deal with Fungus and Finrot, remove the Minnows, Rainbows and Badis, add a little salt, and maintain the system at SG 1.002-1.003.>
I've started to slowly raise the salinity of the quarantine tank, and I'm off to the LFS to pick up the antibiotic and a hydrometer. I believe we have Maracyn and Maracyn II available here (Canada), so I will purchase
A couple more questions, if you'll bear with me:
<Of course.>
Which Maracyn product would be most effective against Columnaris?
<Maracyn rather than Maracyn 2 is usually used first. It contains Erythromycin, which should work on Flexibacter columnaris.>
If the Mollies recover, when would it be safe to place them into my main tank (so that Columnaris does not contaminate that tank).
<Columnaris, like Finrot, is a disease latent in all tanks, and the bacteria involved is presumably harmless most of the time. It appears not because a fish "caught" the disease, but because the fish was somehow
weakened, and its immune system overwhelmed. So provided the other fish are healthy, you shouldn't worry about cross-contamination.>
Thanks again...
<No probs.>
<Cheers, Neale.>
Re: Mollies with Columnaris and Ich - Update 04/03/09

Thanks very much, Neale, for your advice. Just thought I would give you an update on the Mollies. I used the salt + heat treatment for the Ick, and the Ick has disappeared.
For the mouth rot, I couldn't find Maracyn at my LFS, so I used TC capsules (tetracycline). The mouth rot hung around during the course of the treatment (5 days), and then I had an ammonia spike (the packaging on the TC capsules claims that they will not affect the biological filter, but I suspect otherwise).
<Oh dear.>
Unfortunately one of the Mollies died (oddly, it was the healthiest, dominant female).
<Sorry to hear that; I wonder why?>
I subsequently performed 75% water changes for the next several days to control the ammonia, used activated carbon to remove the tetracycline, then added some nice filthy filter media from my other tank to repopulate the nitrifying bacteria. Over the next several days, the mouth rot on the remaining Mollies disappeared, but I'm not sure if I can attribute it to the tetracycline or the water changes.
<It's a combination: the antibiotic kills off the bacteria, but improved water quality allows the fish's immune system to repair the damage and prevent re-infection>
Anyway, the remaining Mollies have recovered, and in a week or so, I will remove them from quarantine and place them in my 40-gallon tank.
Also, you were right, the salt did not seem to affect my plants (Hygrophila polysperma, Hygrophila corymbosa, Rotala rotundifolia, Java Moss, and Bacopa monnieri).
<Not sure about Rotala, but certainly the others are happy in brackish water, let alone slightly salty/warm water of the sort used to treat Ick.>
Thanks again for your help,
<Thanks for the update, Neale.>





Black Molly, dis.   5/10/07 Hi! <Hello!>   I just want to ask about the white and red freaky spots in my black molly's forehead, I change the water and add AquaPlus Water Conditioner a while ago because I am thinking if those spots are wounds. <"Freaky spots" covers a lot of ground. The most common problem "white spot" problems in fishes is Whitespot (or Ick) and Velvet. Whitespot tends to look like crystals of salt on the fish, whereas Velvet is much finer, more like powdered sugar on the fish. Both are relatively easy to treat if caught early. Use commercial remedies, but always remove carbon from the filter before use, because carbon neutralises the medication. The "red" part of your description is unusual though. I don't know any diseases that cause red and white spots. A photo would help.>   Another question is that can they live in a brackish water with a 1-2 tablespoon of synthetic marine salt per gallon? <Mollies not only like marine salt mix but do best in saltwater or brackish water tanks. An ideal amount is 2-5 grammes per litre (0.8-1.2 oz per US gallon). This will help your fish heal quickly and become much more resistant to disease. Other species of fish may not like this much salt, so check that tankmates are salt-tolerant first. Guppies are fine with salt for example, but neon tetras are not.> Last question, can you tell me things to remember to have a healthy and happy black molly. <Please have a look through this article: http://www.wetwebmedia.com/FWSubWebIndex/poeciliids.htm and then take a look at some of the Molly FAQs as well. But basically: mollies like warmth, salty water, high hardness and alkalinity, plenty of green foods, and lots of swimming space. They don't like aggressive tankmates, Nitrates, low temperatures, meat-based flake foods, and soft/acid water.>   I'm sorry for many questions, because I love them very much and I don't want them to die due to diseases. <Questions are good. Happy to help.>   Thanks in advance, and God Bless to all of you! <Cheers, Neale>
Re: Black Molly dis.?  5/13/07
Hi to all crews of WWM again!! <Hello.>   Thanks for your immediate reply! <Cool.>   I can't take pictures of my black mollies because the spots are small, and they are fast moving so now I will just describe it. <What's fast moving? The spots or the fish?> The white spots are in the forehead of my molly they are look like dandruff, not a cotton something. While the red spots are also found in their forehead some says those are wounds. What do you think are those 'freaky spots?' <Impossible to say without seeing them. Holes in the head can be caused by poor water quality, by internal parasites, by physical damage through poor handling, from fighting, from external flukes and lice, etc., etc. Knowing mollies well, I'd put money on a combination of the wrong water chemistry and high nitrates.>   Oh, by the way I bought a marine salt yesterday from the famous petshop in our country. Now the problem'¦how can I put it in my tank that's fully set-up? <Don't add the salt directly to the aquarium, but to the water you add to the aquarium.>   a.)    Will I add the suggested dosage directly to the tank? <No!>   b.)    Will I get a small amount of water in the tank and add the salt on it and pour it in the tank? But the instruction says that I must aerate the water with the diluted marine salt for 30 min.s. <Follow the instructions, but reducing the dose ten-fold, since you only need about 10% seawater for your mollies to really pep up.>   c.)    Will I remove my black mollies in the tank and add the suggested dosage of marine salt in the tank and leave it for a couple of minutes then I will bring back the fish. <If all you have are mollies in the tank (whatever sort) then leave them all in the aquarium.>   d.)    None of the above!! <Here's what you do. Let's say you take out 1 bucket of water from the tank. Dispose of that water. Fill the bucket with fresh water, add dechlorinator, and then add 3 to 5 grammes of marine salt mix per litre of water in the bucket. So if it's a 10 litre bucket, add 30 to 50 grammes of salt. Right, now you need to stir it well, let it sit for 20 minutes, and ideally aerate the water to help it dissolve. If you don't have an airstone, that just give it a vigorous stir every couple of minutes. After 20 minutes it should be nicely dissolved, but check there aren't any grains of salt left at the bottom of the bucket. Assuming it's all dissolved, pour this water into the aquarium. Do this every time you do a water change. Basically you are running a low-salinity brackish water tank, an ideal habitat not just for mollies but a whole host of interesting fishes. Have a read through here: http://www.wetwebmedia.com/BrackishSubWebIndex/bracsystems.htm for more.>   I have an outside hang-on filter with a carbon in its cartridge, will it remove the salt and other trace elements found in the salt or am I just paranoid of that carbon? <Carbon is a waste of time/money and also removes medications making it impossible to treat your fish with the carbon in place. It doesn't really remove inorganic substances (it removes a few, but not many) but it does remove organic substances very effectively. When you add medication to a tank, all the carbon does is mop it up, keeping your fish sick and wasting your money in the process. I despise carbon in freshwater aquaria and recommend you throw it far, far away. Replace the space the carbon was with something more useful, like a bit more biological filtration or some filter floss.>   Last question, my tank is planted with Java Moss; will the plant die if I add marine salt? <Java moss (and also Java ferns) do exceptionally well in brackish water, so not a problem.>   Again thanks for the knowledge, and God may give all of you patience for answering questions!! --Wilvic-- <'Tis fine. Cheers, Neale>
Re: Black Molly
   5/15/07 Hey Neale!! <Hello!>   The "fast moving" I told you are the fishes not the spots, so what is it? and how can I cure it. <Without a picture, difficult to say for sure. If the white spots are like salt grains in size and colour, then it's likely whitespot. If the white spots are irregular and more grey than white, then likely early stages of fungus, which on black mollies is obvious as grey-white patches. In this case, try a combination fungus/finrot medication. Either way, keeping brackish water and raising the temperature (mollies like it warm) will help a great deal. Please see here: http://www.wetwebmedia.com/FWSubWebIndex/poeciliids.htm and the related FAQs.>   You said that I must remove the carbon in my hang-on filter, so what will I use instead of it? <Replace with biological filter media. Filter wool, sponge, ceramic chips. Whatever works for you. Chemical filter media -- carbon and ammonia remover -- don't serve much purpose in most freshwater tanks and you won't miss them.>   Thanks again!! <Cheers, Neale>

Gold Mollies with dry, cracked skin... Nivea solution?  9/18/06 Thank you for your assistance. I have spent endless time on the Internet and have consulted with my local pet store to no avail. I have a 5 gallon tank with 2 gold mollies and 3 guppies. <Hard to keep such small volumes stable, optimized...> The 2 mollies have what appears to be dry, cracked, white skin on the tops of their heads. <Mmm, symptomatic of a few infectious and parasitic possibilities...> A small amount of white was present when I bought them (about 2 months ago). But knowing nothing about fish I didn't recognize this as a problem until the condition got worse. Otherwise they appear to be swimming and eating normally and the condition has not spread to the guppies. Unfortunately, the store I bought the fish from has not been at all helpful in identifying the condition- which is very frustrating since the fish had this problem when I bought them. They just keep selling me more products that haven't solved the problem.  I have tried treating the tank for fungus and ick and have added salt to the water. <Not a fungus or ich... but the salt won't hurt> I have removed the carbon from my filter during the treatments. I have been treating the tank for approximately 1 month. The condition has improved slightly in one molly, but has worsened in the other. At this point I am not only concerned about the white condition, but am also concerned that the filter has not had carbon for the last month (it is a 3-stage filter, so a sponge has been present). <Mmm, actually would need to make a scraping, and take a look/see under a scope to tell much here... culture for definition... But w/o hearing/reading what you've used thus far, under what protocols, am given to suggest a course of Neomycin Sulfate... take a read on the Net re this antibiotic, its uses for ornamental fishes... and the term "Columnaris"... do the pix available, descriptions sound/look familiar here? Bob Fenner>

Re: spinning molly!

Sailfin Molly Illness (02/27/04) Please, help me determine a possible cause of illness in my Sailfin mollies. <Ananda here to help try, with Sabrina helping out...> I have a 55 gallon tank that is brackish.  The contents of the tank are 2 Gourami, 2 red-eye tetra, 4 black Neons, 3 black-skirt tetra, 3 lemon tetra, 2 adult red velvet Platies, 1 Plecostomus, 1 rainbow shark, 4 adult silver mollies, 1 adult Dalmatian molly (lyre-tail) and approx. 15 molly fry. <Uh... the only fish in that whole list that are brackish are the mollies. Platies can tolerate some salt. But the rest of them should not have any salt at all, except perhaps a "tonic" dosage of about 1 tbsp of salt per 10 gallons of tank water. (Which doesn't qualify regarding making the tank brackish.) What's your specific gravity?> All parameters of the tank are stable, all other fish are healthy....except the adult Dalmatian molly.  I have had a total of 4 (including this one) Dalmatian mollies in the past 6 months and at least 2 of them have suffered similar fates.  It starts with patchy loss of scales/color, fins become translucent and there is progressive weight loss.  They still eat and swim normally.  The first one that developed this illness had me so concerned about cross-contamination and looked so pitiful, that I euthanized him.  The first time I've had to do that!  Then the other adult Dalmatian started developing the same symptoms.  None of the other fish in the tank show any signs of illness, and are breeding well.  I'm concerned about fish T.B. <Sabrina and I agree that it does sound like mycobacteriosis.> That is why I didn't want the first sick fish to die in the tank. I read the other fish ingesting the dead sick fish is sometimes the way it is transmitted. <I have read the same thing. You were wise to remove the affected fish from the tank.> This is a very slowly progressing process.  It takes weeks or months before they reach the full extent of the illness.  What is the lifespan of a molly?   <About four years.> Could these fish just be old? <Most mollies I've seen at stores are 6-10 months old.> Why don't any of the other fish display symptoms of illness?   <Mycobacteriosis, aka fish TB, is a funky thing. You can have fish that are infected that display *no* symptoms. Meanwhile, other fish exhibit slowly degenerating health. Sometimes, things progress fairly quickly. And the list of possible symptoms is staggering.> I have treated the tank in the past with antibiotics, Methylene blue or malachite green, and MelaFix.  I can't figure out if it is a parasite or other disease, why it takes so long for it to affect the fish and why other fish aren't simultaneously ill.  What should I do? Debbie Bronson <The best thing to do is try to prevent any more fish from becoming sick. The way to do that is to maintain impeccable water quality; a UV sterilizer *may* help. For you, always wear long-sleeved aquatic gloves while working in the tank and see your physician if you develop any funky bumps on your hands/arms (and do mention the possibility of TB to the physician). The one possibility Sabrina's read about that may possibly cure the disease is Kanamycin, administered in food. However, this does not always work, and can be expensive to boot. If you have fish that exhibit symptoms, it is best to remove them from the main tank. Then, you can either keep them in isolation (possibly attempting to treat them), or euthanize them (I use clove oil; do a search both on the WWM site and at http://wetwebfotos.com/talk for more info). I wish I had better news for you. Fortunately, even though your mollies may be affected, the rest of your fish seem healthy, and you could raise the fry in a different tank. --Ananda>
Sailfin Molly Illness - II - 03/01/04
Thank you so much for your response to my mail.   <Sabrina responding this time, with Ananda shouting from the sidelines.> My error on calling the tank "brackish", I add about 1-2 tbsp. per 10 gallon. <This of course is fine for your freshwater pals.> Since your e-mail, I have euthanized my adult molly that was displaying symptoms. <So sorry to hear that you had to make such a choice; I know it is difficult.> My question now is, are the other tank fish ill as well?   <It is quite possible, if you are dealing with mycobacteriosis; however, they may never exhibit symptoms - or they may all fall ill with it.  The best you can do is to fortify their diet with vitamins, perhaps using a product like Kent's Freshwater Zoe or something like Selcon or Zoe marketed for saltwater use.  Other than that, just keep their tank in tip-top shape.> Will they one by one display symptoms?   <Possible, as above.> Or is it possible that the disease wasn't transmitted?   <Also possible.  Mycobacteria are thought to be perhaps ever-present, and stressed or immunodepressed fish may contract the disease; it is virtually impossible to eliminate this from your tank - likewise, you could not have prevented it, and it's probably floatin' around in my tanks, and certainly in my mucky ponds, and probably most of your friends' tanks, and so forth - healthy fish are the preventative.> Should I assume, at the very least, that the molly fry are infected?   <Again, possible.  Fortify diet with vitamin supplements.  Say, you can even use (human) baby vitamins for soaking fish food (thanks, Gage, for that tip!).> I use a water ionizing system for all water changes, and the tank is impeccable.  I've had multiple broods of mollies, and the red velvets have produced once.  I have to watch the gourami's since they can't resist an "all you can eat fish buffet" of small fry, but I usually put a tank divider in place and sequester the babies until they are of adequate size.   <Sounds good.> I'll look into the Kanamycin just in case.   <While one of my books (Tropical Fishlopaedia, by Bailey and Burgess) suggests Kanamycin, another far more comprehensive text I have (Aquariology: The Science of Fish Health Management, by Dr. Gratzek, et al) suggests Minocycline or Rifampicin used at 0.3 percent in food, treatment to continue for at least three weeks, to be marginally effective....  I do not know how likely it is that any of these treatments may do good - I am under the impression that Minocycline treats only gram-negative bacteria, whereas Mycobacteria is gram-positive.  To be quite honest, I would not treat; I would remove fish if they show signs of illness, and continue upholding excellent fish health and tank maintenance - and do start adding vitamins to your fish foods.  Er, and as Ananda mentioned, wear gloves in your tank.  Or at the very least, wash thoroughly with an antibacterial soap when you mess around in a tank, and if you have cuts on your hands, well, wear gloves.  All aquarists should do so - though, I admit, I am lax in doing so.  'Course, I'll probably find some funky bumps on my fingers, some day....  Wear gloves.> Your team is the greatest.  Deb <Thank you very much for the kind words, Deb.  Wishing the best for you and your fishes,  -Sabrina>

Molly Growth  I have an orange molly fish that developed what looks like a 'growth' coming out of her face, below her eye - like a big orangey bubble - is it a hematoma from a cut or bite? She seems to eat and swim okay but the growth is getting bigger. What is it and does it need treatment? Thanks.  ><<Hello; is the bubble clear? or whitish? If it's whitish, it may simply be lymphocystis, a non-curable disease that usually clears up on its own. If it's clear, like a blister, then it could be an air bubble, due to oversaturation of oxygen and/or other gases in your tank water. I'm sorry I cannot be more specific, since it's impossible to know if this particular bubble is due to your current water, or previous water that the fish was exposed to. Previous exposure should not be an ongoing problem, like I said, unless the bubble ruptures. But if this bubble has recently occurred while the fish was in your tank, you must make sure your water is not oversaturated, because exposure to such water can kill fish, as the gasses will pass into the fishes bloodstream. Make sure your water-change water is well circulated to remove excess gasses before you use it for water changes.  You can try putting it into a bucket and using a simple airstone to aerate the water for a few hours before you use it. The bubble on its face is not a problem unless it ruptures, since it could then become infected with fungus if your water quality isn't good. Also, make sure your tank has enough circulation. The surface of the water should move, but without being a Jacuzzi..:) If need be, you can add a powerhead for more water movement. -Gwen>> 
Molly Growth II 
Thanks for the quick reply, it is a bubble molly and the 'bubble' is more like an opaque growth - like a tumor coming out of the side of her face - almost the size of 3 of her eyes - do you think it is a 'scar' from a bite or an infection growing out of her body? Thx.  <<Hiya, it sounds a bit like a benign tumor, or even lymphocystis, a viral infection that should go away on its own, with good water and low stress levels. Keep an eye on it, and let me know if it changes, grows, discolors, or spreads. Make sure there is no fungus! -Gwen>>

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