IME, there really isn't much of a difference between cardinals and neons besides their appearance. I have never owned rams before, but I would think they'd be fine kept in a pair.ScubaChick0121;4000563; said:Are cardinal tetras more hardier then neons? And would two rams work (one male one female) Or do I need a 1:2 ratio? There would only be one male in the tank.