Aquarium experts of the fediverse we need your help. We have a 60L tank with plants & rocks, only a month old, fully cycled. Got 8 minnows 2 wks ago, all very active and happy. Got home today to find two dead, one sick and one MIA. The others look ok to me. They all seemed absolulely fine at lunchtime.
A few shrimp have quietly died over the last few days and I've been wondering why. The snails all seem completely fine. There's a spray bar and a bubbler, so there should be plenty of oxygen. We've not been sure how much to feed them, and although they feed at the surface they don't catch everything before it reaches the bottom (I assume that's feeding the shrimp). But ammonia has been zero throughout - I've been testing very regularly.
Ammonia 0, nitrite 0.2, nitrate 30. Help! 🐟
@helenczerski sudden seasonal changes in ambient temperature can have a big impact on the fish, even just a few degrees. may not be it, but something to check whether the tank is in a relatively temperature steady spot.