I’ve had a few shrimp deaths recently so did a water test today, only to find that it looks like there is ammonia in the tank. It’s reading at .25. I have no idea why there would be ammonia. The tank hasn’t had ammonia since it was cycled 9 months ago. It’s had shrimp for maybe six months. The only other occupants were a few molly fry which i removed over the weekend when i realized he was large enough to suck down baby shrimplets. I think maybe some of the issue is buildup of waste under the gravel since i’m afraid to go crazy with the vacuum when there are tiny shrimp everywhere. The java moss is kinda new and doesn’t seem to be doing great, so maybe if that’s dying it could cause visible ammonia? I feed them barely anything, a shrimp pellet or some kale every few days. Question: how big/how frequently is it safe to do water changes? I usually do 10% once or twice a week since i don’t want to shock them. I am thinking of doing 10% the next few days and using Prime. other parameters since i know people will ask: pH: 6.6 ammonia: .25 nitrite: 0 nitrate: 5 gH: 100ppm kH: 50 ppm Ten gallon tank includes neo shrimp, a bunch of duckweed and floating red rooters, some swords, red tiger lotus, java moss, pest snails.