Noj,
You're welcome
After three weeks, most of the crud has already broken down into nitrate and phosphate. We siphon out our tanks weekly to keep nutrient levels to a minimum. Having non-invasive macroalgae in the tanks help with nutrient levels as well.
Here is our (cough) very long page on how we maintain our three tanks. Lots of pics, probably waaaaaay too many words.....
http://www.lostmymarblz.com/reeftips...ottomtanks.htm