Anyone know of a decent float valve?    I've got a Petersen concrete waterer with a Franklin valve and it's worthless.   It gets sand stuck in it and it won't open up far enough to fill fast, and it won't close completely so it always runs over.  As I said, we do have a small amount of fine sand in our water but nothing serious.   I see Valley Vet has a few options but not sure they are any better than what I've got.   Any help appreciated.