thanks guys, it's been about 4 days since i installed the hoppers and they do indeed seem to work well. the only reason i want to use food hoppers as opposed to just putting the food on the ground is because we keep the rat bins inside and after about a week or so i end up having to replace ALL the substrate, and there is lots of food mixed in that i would just have to throw away if i didn't use hoppers. the 1/4" hoppers i made are probably going to last a litter of fifteen 30ish gram rats about a week. and i have a 1.1 pair in a separate tank that i'm going to retire as soon as these little ones are growed up enough to start producing. i'm thinking of keeping a 1.3 ratio in a 64 quart sterilite latch box. so we shall see how that works out. i'm very new to this