It's a old rule I heard a long time ago as a kid. I didn't think anyone still used it though. But the person who owns this place, says that they don't want any aquariums or stuff like that in the house. I talked to the lady who owns it. They said they had a couple people before who owned fish tanks and they made the place smell really bad, like a fish store. I told her I use to breed Betta Fish and never had the house smell at all. But the point is she letting me keep my dogs and that's o ready pushing it, so I gotta cave and let the frog go.