It should be fine. It all depends on the dispositions of the horses.
We keep our 2 geldings and 2 mares together and they get along fine....they just all keep out of Sugars way :P
But theres really no problem that I can see with it.
More often than not I find that a mare and a gelding will get along better than two mares. However, I have known some geldings that can't Ben with mares without always mounting them. The particular horse I'm talking about was a stallion until he was eight though.
We have senile old boy who has decided he is a stallion again. As long as he's with his wives he's happy, he was chasing the other gelding away so we moved him. If left with no wives he screams and runs the fence.
It works well though because the 3 mares are never all out at once. We have had to resort to tying him on the same side of the float as prin when we're out but he's happy there. Posted via Mobile Device