Huh. Never even thought of that. I watch my haps and mbuna in my show tanks pick at the algae on the rocks so if they will accept them for food feed it to them.
Oh yeah, when I feed my Bn pleco the algae wafers my africans peck at the wafers like there is no tomorrow. They are always greedy when it comes to algae wafers. I say it's okay since mbuna need vegetable matter in their diet.