Growernut, have you tried using mosquito dunks? They are disks that you float in your water tanks that prevent mosquitos from laying eggs and breeding. They are animal friendly. I bought some for a friend who has a slow, almost stagnant,stream in her back yard. You can find them in feed stores, Wal-Mart, or on-line at Amazon or other places. I know a lot of horse people who use them.

Bonnie

thanks, i will check those out. have not heard of them before.

I've had good luck with goldfish in my stock tank. The horses or cows don't drink them.

I use about a half of a plastic cup of clorox about once a week, depending on temps. Actually, the bull gets mad when it is about time to add clorox. He will butt the tank and let you know! He is a trip anyway. I have to fill up the tank every other day in Florida, they will drink about half of it. I have 2 cows.

Yes, and lately I am trying calcium hypochlorite tablets. They work better and faster to kill all sorts of stuff in this very hot, dry, drought weather we are having. Just hope it doesn't kill the animals also. I put in a tablet and run clean water for about 24 hours in my very large water tanks--we'll see if it keeps the water clean without killing my horses. Will probably only use one per season.

We have automatic waterers,nice you just have to flush out occasionally