So lately I've been on a bit of a cleanliness kick in my forts, in no small part because I've heard rumors that contaminants can really drag down your frame rate.
Mostly I use the trick of a wading pool connected by lever-controlled hatch or floodgate to a windmill-powered permanently-running pump. Have the dwarves fill the pool to 3/7 or thereabouts by bucket brigade, wait until it's thick with blood and other whatevers, then drain it by pump. This leaves the floor of the pond (and the ramps, and the walls around it) covered in contaminants, so I set a meeting area at the bottom of the pond and wait for the dwarves to clean it by hand.
Surely there's a better way.
I've thought of using a drawbridge as an atom smasher, but I tend to have bad luck with those. Then I thought of coupling it with a panic-room burrow that I could force all my dwarves into with an alert … but that's just as big a pain as draining it and having the dwarves clean it, really. Plus which, it can't destroy contaminants on the ramps on either end of the pool.
Then I thought of using pumps to create permanent flow which carries the contaminants through a grate and onto an atom smasher I could safely trigger any time … but contaminants don't flow through grates. Plus, I've had a devil of a time so far figuring out how to create continuous flow while keeping the water level below the 4/7 "can't path through that" limit that shuts down traffic. Since it doesn't seem like that can solve the problem anyway, with the grate issue, I suspended that job and went searching for a better solution.
Before I dedicate a lot of time to !!SCIENCE!! trying to figure it out on my own, I thought I'd ask the hive mind. Other than manual cleaning (which is spotty) and atom-smashing (which is no more convenient than manual cleaning, it seems), what destroys contaminants? Is there a well-known clever idiom for this that's already out there?