I don't know anything about rays so i'm not sure if this is a stupid question, are there any rays that would go in a 90g tank for life?
I always hate when the minimum tank size question is asked. Just totally torques me off! What do you suppose a minimum housing size question for you would be? Would you like to live in the minimum? Ok they produce alot of waste which is part of the housing requirnment needing to be big. Minimum probably a 125 but I don't think they would be very healthy long term being exposed to high levels of bad stuff. Probably a 180 is about as small as I would go for life even on the smaller species. I have retic's and Hystrix in a 500 with 180 sump. My big female retic is over 14 inch plus tail size and my hystrix is over 15 plus tail.