I'm looking at adding a school of harlequin rasboras to my 20 gallon high tank. Right now it is stocked with 2 Bolivian Rams and 8 cherry barbs. I'd like some more fish in the top third of the tank and to have some that somewhat school together sometimes like the rasboras do because the cherry barbs roam about by themselves usually in the middle to bottom third of the tank.

Do you I have room to add 8-10 harlequin rasboras?