New growth a little problem


Junior Poster
Mar 27, 2005
I have been noticing dwarfed growth from some of the plants in my tank. The new growth is almost like the dwarfed version of its normal size.
I have rock hard water here so I dont think magnesium or calcium is a problem.

Im guessing stunted growth?..

Heres what Im dosing: All greg watson ferts

Iron Chelate(1 tbs mixed into 250 ml od distilled water) 1.5ML 3xweekly
CSM+B(same mix solution) 5ML 3xweekly

KH2PO4 1/8 tsp 3xweekly
K2SO4 little over 1/2 tsp 3xweekly

I dont dose nitrate because of bio-mass, stays roughly around 5-10ppm

Ill post some pics tommorow to help better explain my ordeal

Tom Barr

Staff member
Jan 23, 2005
Dwarfism tends to be classic CO2 deficiency.
Low NO3 can cause this as well, but CO2 is far more common.

I've taken plants grown in the CO2 rich tanks and placed them into the same type of tank but no CO2/water changes etc. They all gfet the classic dwarf appearance.

Be careful with not adding KNO3, the NO3 test kits are particularly poor at the extreme ends of their ranges => the low and high ends.

This is true for any and all test methods.

I think many can eyeball a tank and know if adding KNO3 is required.

However...... adding more KNO3(say 10ppm extra week etc) should not have a negative effect on a tank either way.

There should be now negative effect from 20ppm NO3 vs 30ppm NO3 in other words.

If your kit is off by 10ppm, then that gives some buffer and about a 3 day supply under higher growth conditions before trouble starts.

The real question is is adding a bit more harmful? What can be gained by adding a tad more? Is it hard and is it worth the trade off?

I certainly think it is and have never seen anything negative impacts due to adding 10-20ppm extra per week.

If folks do see negative impacts from this, then they where very limited NO3 or perhaps K(easy to figure which one by adding K2SO4 instead) and adding it increased the CO2 demand etc, then that, not excess NO3, led to the issues
you can easily have low PO4/Fe/NO3 etc if you are low on CO2 or light.

As you have more light, you nered more CO2, as you add more light/CO2, now you need more N, some can come from the tap or fish waste etc or add another 10ppm if not sure for the tank using KNO3.

If you limit one nutrient, then the uptake of the others will be reduced.
That can cause NH4 to linger and not be removed nearly as fast from the fish waste and turn into NO3 or induce algae spores.

There is nothing wrong running a tank with fish waste, or lean etc, but there is a trade off and kno0wing what negative effect of higher levels is reasonable question to ask your less, less is not always better.

Many want less NO3, but more light, or higher CO2 but less PO4.
That always leaves me scratchin my head.

Run everything(klight/CO2/nutrients) lean if that's the goal, or run everything richer.
Neither method will give you algae and both can produce a nice tank done correctly.

I generally suggest starting with a goal in mind, then stick with an overall approach, not piece mealing parts of one method and adding to another.

A middle ground approach would be using Excel in lower light tank or CO2 in lower light tank etc.

Some are finally revisiting the virtues of lowering lighting recently.
You might even try lowering the amount of light and that often will reduce the dwarfism. Then you know it's CO2.

Tom Barr


Junior Poster
Mar 27, 2005
Always great feed back Mr. Barr!

I think my co2 levels are pretty much in check. I have a drop checker present and has the KH standards solution in it. The solution stays a nice bright green. My measured pH is 6.3 with a KHin the low double digits(10-12), that area.

I also dose excell on a reagular basis at its recommended amount. Mainly to help fight and prevent BBA on slow growing anubias and such. I know you stress the importance of a plentyful and constant amount of cO2 supply in aquariums and I have stressed it to myself of maintaining such levels.

I have read many of your posts an articles about getting the red to pop on certain plants. I've tried to keep my KNO3 as low as possible without giving BGA a window of opportunity. Im hoping to get my colorata, rotundifolia, and arcuata to show their potential.
For some reason, Im not anywhere close to what I have seen them at. I have a high-light set up(4x39watt T5) so I dont think thats my problem. I have yet to clean my tubing from filters because I didnt want to disrupt any of the Beny bacteria present, but know some of the KNO3 is present in the gunk.

I do see your point though about having everything on a level playing field as far as high-light, nutrients, ect.

You replied to another post of my about switching over ffrom GW dry ferts to ADA liquid ferts. Again not saying that I have been unsatisfied with GW ferts, had nothing but great results! I was curious about the addition of ECA and its effects on red pigment plants. Also the "natural" contents mentioned in the ingredients of the ADA line. You suggested a DIY "ECA" but I am no where near a chemical scientist and probably have a meltdown of algae if it was up to me creat a formula of stuff.

Anyways, thats my end of it. Hope to get further detail about the subject :D

Going back to the topic at hand, what would be a nice amount(KNo3) to add into the tank and not comprimise the reds int he process? I originally was dosing about 1/2 tsp and noticed the colorata going completly green.