So i have a 30 gallon long fish tank that has 1 BN pleco,1 red tailed shark,3 kuhli loaches,3 nerite snails,1 panda cory,1emerald cory,1 peppered cory,1 juli cory, and 1 albino cory. I got 5 different types of cories because the the guy at petsmart said they would all school together,but he was...