I have a 5 gallon tank with 10 animals total(3 ruby tetras, 2 guppies, 4 cherry shrimp and 1 ramshorn), which I have had for about 2 weeks now. So far, I've noticed there's been an algae buildup on the sides of the tank, and on the rocks. I'm pretty sure it's brown algae but I can't be certain. Also, did I overstock the tank?