I have a 25g refugium attached to my main system. It has chaeto and a 5" sand bed. I prune the chaeto every week, so there's plenty of swimming room in the fuge. Two weeks ago, I put 5 cardinals in the fuge, and they've all been dying. The snails in the fuge aren't dying, and the fish in my main system are all doing fine. Does anyone have any idea what's going on?
The only thing I can think of is maybe there's not enough oxygen in the water. The turnover in the fuge is very low, and there's nothing that disturbs the water's surface.
The only thing I can think of is maybe there's not enough oxygen in the water. The turnover in the fuge is very low, and there's nothing that disturbs the water's surface.