Dying catfish.

Question
Hi! I just went fishing recently with my dad at Suson park. We were walking to our usual spot when my sister spotted 2 dead cat fish.They were on there backs, eyes completely white,mouths open,and gills mutilated inside. we thought nothing of it and moved to another pond. when we got to that pond my brother said eww and I looked over. Another ne was there with the same "symptoms" as the other 2 fish. My dad very confused moved to yet another pond. There we found 2 more with the exact same things as the other 3. My family and I started getting creeped out and annoyed. I have never seen something like this before. Then when we were about to leave I saw a catfish swimming around. My dad was worried because it was swimming close up to the top and slowly. When my brother said "Hey dad! Can you help this fish?" I came running. A new catfish was turned over with one of its gills sticking out of the water and gasping for breath. My dad picked it up and hurriedly put it in the water. None of the other fish had any symptoms like this and were swimming around fine. I love fish and it was very sad and confusing to see them in this state of death. What was happening?

Answer
Hi Miranda,
 It is hard for me to say without seeing the situation but a likely cause for such a thing would be a lack of oxygen in the water. If it is hot out and the water is not moving very much (as often happens in ponds), then the amount of oxygen can get very low -- too low for some fish.

-- Ron C.
  rcoleman@cichlidresearch.com
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