my tank‘s two years old and recently my fish have started dying despite no changes that i can see when testing my water, everything’s seemingly stable with no elevated nitrates or ammonia. the counter my tank is on was pretty full until just now when i cleared it so i couldn’t see the sand for a minute, now i see these bubbles… is there something that could be released from these bubbles that wouldn’t show up on a standard freshwater aquarium test kit and harm my fish? if so, how long should they be removed from the tank and the sand be stirred before adding them back?
Posted by surfa220
4 Comments
It could be hydrogen sulfide bubbles, when you pop or disturb them does it smell like rotten eggs?
the problem is the combination of anaerobic pockets in which organics are captured. Anaerobic pockets actually contain bacteria that eat nitrate. That is how deep substrate beds work to help filter the water. The bacteria produces nitrogen gas which *dissipates off. The problem is when organics are trapped in there it switches and started to produce hydrogen sulphide. Hydrogen sulphide is extremely toxic. Most will just gas off, but some will get absorbed or your fish will swim through the bubbles and can cause problems. Possibly could be the issue. Malyasain trumpet snails churn ur soil and help with this there are also probably other solutions.
If you suspect your sandy soil substrate is compacting in the deeper sections, you can take a water sample near the bottom of the tank.
Just take a pipette and cover the tip with your finger. Reach down to the sandy substrate level and get a water sample from above the sand or in the sand. Test for ammonia.
If it is reading ammonia i would either remove some sand to lighten the compacting soil at the deeper levels, add some deep rooting plants, or remove the sand entirely and go for aquasoil.
Aquasoil does not compact as fast as sand. It is light and the balls are large and irregular to allow for good aeration.
Some deep rooting robust plants are cryptocoryne and staurogyne repens. But they like oxygen at their roots as well. Most plants do.
If the fish are already gone, stir up the sand quite a bit change the water throw in an air stone help it gas off maybe get some Malaysian trumpet snails some people hate them, but they’re a lifesaver with a planted tank with a deep substrate