LOL. Yes, the creatures marketed to help keep your tank clean. I have countless plecos, and I think we just started recording who found the longest strings of poop in order to make the clean up a little more interesting. So far, I think we found a 14" shoe string piece of poop that came out of 7" Gibby. 
We just keep the tank planted with anubius, and have lots of filtration. I have found that although there is a lot of waste, it really isnt as harmful as say a straight carnivore. A lot of that coming out is wood and not high in digested proteins. So actually, the ammonia build up doesn't seem to be nearly as great as you would first imagine. However, you'll get used to huge shoe strings of poop all over the tank, and, eventually, its not so eye pooping... I mean popping. 
We just keep the tank planted with anubius, and have lots of filtration. I have found that although there is a lot of waste, it really isnt as harmful as say a straight carnivore. A lot of that coming out is wood and not high in digested proteins. So actually, the ammonia build up doesn't seem to be nearly as great as you would first imagine. However, you'll get used to huge shoe strings of poop all over the tank, and, eventually, its not so eye pooping... I mean popping. 