Introducing a newbie from Minnesota

[Kelfin]

My welcome letter suggested I post a hello to everyone, so Hello!

I have a single 20 gallon freshwater tank with some miscellaneous fish in it - we have a large angel fish and a plecostomus (named "basketball hoop" by my kids), plus a zebra fish, a pink something I forget the name of, several swordtails, and two ghost glasscats.

I found the forum looking for information on minx algae (mynks? minks?), which is what my fish store guy said the black fur taking over my tank is called. If anyone can tell me more, I'd love to know!

I also discovered today that my last remaining zebra looks bent in the middle. Is this that same weird problem that happens to dolphins and sharks, or is it pregnant, or a harbinger of tank doom? Anyone?

Thanks!