Have you tested the water? The chemistry or even the temperature of the water since we've had some cold ones lately. I believe this shop offers water testing if you being them a 5ml sample, or they sell the kits for you to do at home.
Sorry about your fish. Call and ask, Cory is very knowledgeable and should be able to help you fight out. Good luck.
Call the shop. The staff is always helpful and knowledgeable.
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