I'm frustrated with the problem of diatoms. I'm pretty sure that's what it is since it's powdery brown in color and blows away with the turkey baster. I've religiously been doing water changes (20% in my 24 gallon nano each week), feeding every 2-3 days. I do have my lights on 9 hours a day because of corals but even before I added the corals, I still had the diatom problem. I've increased my cleaning crew (4 Mexican turbos, 4 nassarius, 10 astria snails, about 15 red and blue hermit crabs, 2 peppermint shrimp). I'm feeding a combination of mysis or pellets (New Life Spectrum - recommended by lfs) and occassionally Rod's Reef for the corals. I don't rinse the frozen. My levels last week were: nitrate 5, ammonia 0, calcium 400, ph 7.4. I can't remember my phosphate level but it was a normal reading. I'm due for a water change Monday. I also have a small spot of hair algae on one rock (strands about the diameter of a dime) that I keep pulling off by hand but regrows. My tank has been up since August. I know that a "new" tank has diatoms but should I still be having this issue. Does this mean my food quality is a problem? Corals and fish are all healthy but the diatoms look ugly! Oh, and I have a nano protein skimmer. I clean it every week but it does seem to put out a lot of micro bubbles. I've tried replacing the bubble pad. Experts??