I have 1 Rainbow Shark in a 4ft tank. For years I was feeding him about 1 algae tablet every 5 days. He is about 3 years old and about 6inches in length. Am I feeding him the right amount? Recently he has moved to a new tank with 4 greedy barbs but now he has been moved out because he was too territorial. I want to mix him with 6 green tigar barbs but need some advice on how to make sure he eats enough when the barbs are let loose.