system
Given the following post, respond as if you're commenting on Reddit:
human
[Stargate SG-1] Why didn't the Asgard used older DNA samples for there cloning?

As we know the Asgard used cloning as means of procreation or rather sustain there species. 

Sadly since they where using the DNA provided by the previous clone there species started to deteriorate. Carter compares it to "making a copy of a copy of a copy".

I know that when they started to use cloning they didn't know the risk involved but once the problem was discovered shouldn't they have just save up the oldest clones of each Asgard and used there DNA as basis for the next clone?

Maybe not solving the problem but permanently halting it. We know that they posses perfect stasis technology even better then that of the Ancient.

In an Ancient stasis capsule you still age although drastically slowed down but an Asgard stasis capsule keep you in stasis perfectly with minimal energy since they recovered an ancient Asgardien from a ship that crashed thousand of years ago.

Secondary question: If they found and ancient Asgardien why didn't they just started to clone him for all Asgards? Genetic diversity is only needed if you procreate sexually.
gpt
DNA is only part of the problem. The other problem is that Asgard bodies (as they existed in the early 21st century) were the only kind that could safely house Asgard *minds*. 

The Asgard have spent millenia copying their memories and personalities into cloned bodies to achieve immortality. They can't survive any other way, because of the centuries their own minds have incrementally adapted to living in a very specific kind of biological hardware. It's not possible to just copy some 8,000 year old DNA and stick an Asgard mind into it. The brain isn't advanced enough - the mind wouldn't really "fit" in it. 

Think of computers: You find out that your current PC is putting out a mild form a radiation that's actually causing damage to the hard drive, causing minor but increasing damage to the files, and the damage is duplicated every time you copy them. You need a new file storage solution - but all your programs that would help you design a new system have been damaged, and all schematics for older models were purged years ago because you thought you didn't need them.

All you can do is look around for an older but more reliable storage system. After a few years, you find one magnetic tape storage system from 1985. This system isn't vulnerable to that radiation damage, but it's also nowhere near the storage capacity you need. It's all you've found, but it'll take a long time study it to the point that you can make new ones that are large and fast enough to suit your needs.