1 of the 4 redside dace in my 20 high isn't doing to good. It hasn't eaten since I added it last Tuesday, its caudal peduncle and caudal fin appear to be much paler than the rest of it, and it's having a harder time swimming. I think it's pretty much to late but I wanted to check if there was anything I could do for it. It's in a heavily planted 24"x12"x16" with tankmates of 3 other redside dace, 4 silverjaw minnows, 2 Greenside darters, 2 swamp darters, 1 rainbow darter, 2 bluefin killifish, and 1 Pugnose minnow (I know that sounds overstocked but they're all fairly small with the sick 3.5" dace being the largest fish and I'm upgrading to a 30L very soon). Filtration is a sponge and a lot of plants including hornwort, water sprite, and carpet algae and I do 50% WCs once a week. Any suggestions or advice at all would be much appreciated!
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