I haven't had trouble with Corys in general, we have panda corys in a 46 and sterbai in a 200. I fed some extra bottom feeder this morning just to make sure they got some food.I have 13 of them in a 20 gallon shrimp tank that I bought in two different groups and haven't lost a one. However, I was losing all kinds of Corys in my big tank until I started feeding them the Sera O-Nip Treat Tablets and Shrimp Pellets because none of the flake food was making it to the bottom.
What kind of Corys do you have? My pH h as been pretty stable. I haven't done a water change since I added them in but I'm due for a change.I have had a lot of trouble with cory cats in my 10-gal I believe when I perform water changes the slight change in ph from the tap stresses and kills them off I have little evidence to prove this as the cory cats have been the only species I have had trouble keeping alive.
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