17 fish dead!
My fish are in my basement in a 300 gal tank. When I went to feed them Saturday morning 17 were dead sucked against the pump outake. Lost my 1 koi, Scoop 12" long, all my white sarassa comets, wakin and goldfish. Most of these fish are 7 to 9 years old. I'm not sure what killed them either a major amonia spike or oxygen deprivation. I did a major water change and salted the tank for the remaining fish. This morning the fluval filter/pump I run on this tank wasn't working so I cleaned it. I am wondering if the pump shut down and oxygen deprivation killed the fish. Their kills were very red and the gill plate white along the edges. Amazingly the shubunkin survived or at least 3 of them and are doing fine. So thats at least $500 in fish as the goldfish were between 5 and 6" not including the tail.