Also besides these two tangs, what would be another good large(non shrimp and snail eating) fish to have. I would like to have a butterfly of somesorts or a rabbitfish. And I had an idea for water turnover, The tank has 3 1 and 1/2 in overflow holes in the top. I am going to use the outside holes as the siumps intake and the center hole as the return. On the inside of the tank could I glue a piece of pvc
leading to the bottom so that it takes water from the surface and returns it to the bottom?