I'm still in the process of building my basement, and as I design walls I'm trying to get a good idea of how big I need to go. I had to scratch my 850g build because my wife wants a pantry. Now with a new wall going up, I was going to build a 200g(7x2x3) into the back wall. I still haven't decided on my stock, but my visit to my LFS over the weekend I saw rays and aro's and thought maybe two aro's and a ray would be nice. I know ray's are picky about water, and with their roaming habits they shouldn't cross paths. But is 200g enough?