What does it mean when people say Pleco's will "foul" small tanks?

[cherryshrimp]

Rainbowfish don't normally get Columnaris. They do bump into things and get puffy white lips, this is bruising and goes away on its own. Some salt in their tank can help them heal up too.

Post some pictures and a short video if you have sick fish. Having people guess at diseases based on symptoms is a good way to get an incorrect diagnosis.

I came back to the tank she is laying upside down. She got up to swim and is moving now, but she can’t stay upright. Can’t get a good pic cause the light is off but she has cottony tufts coming from her mouth. They developed yesterday, and were worse this morning. I dosed Maracyn 2 since it’s the best anti biotic I have on hand to treat it.