12 gallon bookshelf aquamaxx tank .. struggling with some blackbeard im guessing . Try and dip in peroxide and dose excel everyday but it's coming back . I dont get nearly as stressed with the freshwater though as long as u dint see a strand of algae in my reef then I'll be mad lol. Anyways , 6 celestial pearl danios, 3 ember tetras 2 cory cats pair of red shoulder mcmasteri apistogramma, and 4 rummynose .