Virginia says: My horses have a drink after they eat or graze but overall they're not drinking a lot of water compared to the reading I've been doing about all the gallons of water a horse needs per day.
Congratulations on having your horses at home! My favourite thing is to look out the window and see 5 heads bent to graze! My horses aren't drinking from the water trough much at all right now. I am in Southern Ontario. They still have loose poop from all of the grass, so I don't worry about it. When It gets hot they will drink more, especially if the water is cool. In the winter I find they prefer warm H2O. Since you're keeping the manure around, I have had good luck with fly parasites. I spread them on the manure every couple of weeks and it seems to make a big difference. It costs about $30 every two weeks, but we are all happier for it. I start mid may and finish in October. Laura - with Atli and Bjalla