My cories eat good food. Cories aren't just scavengers. They need high quality food like any other fish. So they get frozen bloodworms, brine shrimp flakes, algae wafers, shrimp pellets, etc. I do two large water changes/week in both tanks that house cories. I think it's a combination of being in top condition from good feedings and all that fresh water. When I do waterchanges, its 40-50% in each tank 2X/week. It is very difficult to get survivors in a community tank with hungry fish!!
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