For those who use black mollies to help keep you macro algae clean of nuisance algae, how effective are they? I tried a black balloon molly and i cant tell if its making an impact. It just hides from the clowns durring the day and comes out at night. Also, is there anything special about black mollies vs other types such as balloon, sailfin, lyretail ect in terms of their affinity for algae?