If you mean installing and taking care of them in homes and buisness,then i was one of those. Get ready for odd hours late nights you have to go in and clean,test water after hours. There is good money if you are a contracter (licenced) and do saltwater,saltwater is key to big money doctor offices love salt tanks that is where you would direct your advertisement and a wife as a secretary for spelling and gramer as you can read.Oh yea you must Must! have flood insurance if a tank leaks they will blame you everytime, cover these bases and it can be alot of fun.