Don't go by other sites as they will give minimums, and we all know minimums suck. We could all live just fine a 4x4 bathroom but we would be pissed as hell and deprived in numerous ways. Get the biggest tank you can afford and you have the room for. Smallest rays that are easiest to come by with the best price tag are of course retic. I am a huge promotor of retics but I think I am by far in the minority there. I have had nothing but good luck with them. Hardiest ray is the motoro and still a decent price tag on them but they get quite a bit bigger. My retics which are supposed to be smaller rays my female is over 14 inch disk size so that isn't all that small. But please read every sticky that is available and after youhave read through them once or twice feel free to ask more questions. Welcome to the addiction!