i have a 20gal. tank that was once used to keep a piranha but i got him a bigger tank and was looking to get a couple albino pacmans. can i put both of them in the same tank or do they need to be separated? and after reading some other threads i think i have a pretty good grasp on their diet and tank set up other than lighting and heating so if i could get a little info on those two things as well that would be great!

thanks!