hard to really answer that? genetics play a part, they do keep growing, he may never reach 10" or may reach the 18" and how long is hard to answer. keep an eye on Craig list. all my tanks from craigs, my 175 was 200.0 with a hard wired stand and pumps. just put 20 or so away a month in your mad money stash, as i call it. and watch craigs list. I have my eye on it know. looking for a 150 tall for the babie JD pair that aint so much babie JD anymore. for now plec and oscar fine for the tank. wc schedule will be once a week, long as you watch feeding.