I use a 20 aquaclear on mine so i can run carbon or use some biological sponge. heater and a fake plastic cave
I tear mine down and clean after each use.
If you leave it up you'd need to add a lil food now and then.
You can use a dirty sponge from your tank for a bio filter and that will cut way down on water changes. but if you use copper it will kill your biofilter and cause ammonia...
If you use copper you need to do water changes. (i do every other day)
But you have to re add the copper you took out without overdoseing.
heres a super acticle.
http://www.reefland.com/forum/marine...e-process.html