(not trying to be a smart ass)
If you are "using" plecos... I am guessing that you are under the understanding that they clean the tank. Generally speaking, this is not true. Some will help to control algae, but that is it.
In general... plecos are the same as other fish. The do poop a LOT.
I went through a phase and got a few of the more exotic (not crazy expensive though) plecos. The problem with keeping them with cichlids... at least Africans... they like soft water (from the Amazon mostly) and Africans like hard water. Not the best mix.
The worst part of them for me... they hide so much. But, they need to hide to stay happy and healthy.