Your probably pretty close. Whats the rule of thumb guys something like 2 inches of fish per gallon? I think thats it, and since Plecks and Angels actually poop enough for 2 fish Id stop there. Do you have any pics?
The "rule" is 1 inch of mature fish per gallon...but that rule is so generalized it can lead to some major headaches. Plecos are much more "messy" than other fish.