I had my 24 gal Pod running since Feb. 26th 2006. I added a protein skimmer just the other day. Does the skimmer strip the tanks of nutrients. I want to start a reef tank. What supplements should be put into the system? I have about 27lbs of LR and 20lds of LS. My ammonia are at 0ppm nitrites at 0ppm but since I disturbed the system by removing the stock sponges ( I heard they are nitrate troubles) my nitrates stayed at 20ppm. Before I removed the sponges the nitrates were at 0ppm. Anyone Please let me know thanks