So I was considering setting up a rubbermaid 300 gallon stock tank and one of the fish I would like to stock it with is either a RTC/TSN cross or a RTC. Now I know the stock tank wont be large enough to house one of these fish for life but roughly how long are we talking before having to up the ante again? I dont know if I could upgrade within a couple years after the 300 so do you all think I could house one of these fish happily in the 300 for maybe 4-5 years or will I have to look for an upgrade within a few years or so?