They are nice to look at, but as you said they produce a HUGE amount of waste.
In my 55 gal I have one pleco and one scomb with rather high nitrate levels. He produces a lot of waste but I cant bring myself to getting rid of him even though there is a lot of poop around the tank almost always.
With an aerator, and power head I have to remove the sponge I put on their intakes almost every day to remove the stuff that sticks onto it.
So its up to you, the mold or algae may come back if you decide to remove them keep in mind.
You can try not feeding them as much which will reduce the amount of waste but don't over do this one.
But personally, I just do 50% water changes every week and vac all of his "left overs" in the process.
What i do doesn't really solve the problem, but it makes the environment livable for both fish which is my primary concern.