How many C. sterbai, max would you recommend in a 20 gal. 24"x12"x16" tank?

Hello, I was wondering if anyone knows how good importers quarantine there plecos? (feeding,medication,ect.)if medication is used, what type?

It would help to know what kind of catfish you want to keep in order for someone to make some recommendations.

A friend of mine has a breeding pair of angels in a 55 gallon tank,that is all that is in it. I let him borrow my Aqualog all L#, so he could look at it, now he wants to add an L-200 and a L-007 in with the angels. I told him that I did not think that would be a good idea. I am wanting to get your ...