Eight clowns in one tank?!?!?! :scared: No way. Especially when one pair is maroon. They are very territorial and will kill any other clowns that get near them.
As for the individual anemone thing, many percs and ocelarius clowns will not host in one for whatever reason. In addition, anemones move on their own. Eventually they will end up near another one and then you will have a battle on your hands!!
In a tank that size, you may get away with percs and tomatoes, or tomatoes and ocellarius, but I would limit it to that. The tomatoes will readily host so another pair of clowns (except maroons) would learn quickly to stay away from them and their anemone.