Just moved my 5 over from boarding to my new barn on own property. At boarding, they would put mosquito fish in stock tanks to eat the mosquito larve. I have done the same with my stock tank in pasture, but noticed several have already gone to the great stock tank in the sky! Don't want to drain the tank because of the live ones and using a fish net is a pain. Question is in a 50 gallon stock tank, would 10-15 dead mosquito fish pollute the water to such a degree that is it not good for the horses?
Yeah, get them out of there. You could try siphoning some of the water off first to make things a bit easier on you, or get a large piece of netting/screening and drag it across the tank to corral everyone living and dead into a smaller area.