Well, I've had a nice, easy-to-maintain 20G non-CO2 tank for about 4 to 5 months. It's been great not having to do water changes at all and only pruning once or twice a month. I started out with 21 galaxy rasboras (Celestial Pearl Danios for some of you) and a few nerite snails. I did a very light EI fertilizing -- my nitrates would go down to zero if I backed off of fertilizing for a week or two. All was as I had hoped.
However, I had a very small amount of thread algae on the plants near the surface. So, I thought, "Hey, I'll get a few shrimp." I went out and bought 6 tiger shrimp. No algae anywhere in a short time. A few months later... I now have about 50 tiger shrimp (damn little rabbits). I'm no longer dosing KNO3 and I started checking my nitrates, which have been slowly building and are now somewhere around 50 to 60ppm. (And, Hoppy, before you ask...YES, I did calibrate my nitrate test kit!
) Looks like my bioload is now too much, and I'm back to having to do water changes. Long term, I think I'll go to Amano shrimp and take the tigers back to the LFS.
However, I had a very small amount of thread algae on the plants near the surface. So, I thought, "Hey, I'll get a few shrimp." I went out and bought 6 tiger shrimp. No algae anywhere in a short time. A few months later... I now have about 50 tiger shrimp (damn little rabbits). I'm no longer dosing KNO3 and I started checking my nitrates, which have been slowly building and are now somewhere around 50 to 60ppm. (And, Hoppy, before you ask...YES, I did calibrate my nitrate test kit!