I just wanted to say a very very special thank you for all of the replies I've received from you guys on "diatoms"...and Steve...I think you hit the nail right on the head when you suggested RO/DI water to rid myself of diatoms. I went down to one of our biggest water companies here in the Bahamas, "Aquapure" and bought 20 gallons of RO/DI water and did a 20 gallon water change (The water sells for $0.75 a gallon and they deliver right to my door step, 5 gallon bottles). During this process, I rinsed off as many rocks as I possibly could and siphoned of my sand and it's been over 24 hrs now, and I see nothing new (diatoms) springing up. Usually by atleast 8 hrs after rinsing off some of my rocks and siphoning off my sand, the "brown nuisance" will almost all be right back to where I was before I started. I will probably do another 10 gallon water change in about 3 more days and so on (if need) to see if I can gradually wash out all that old water. I would do a larger water change, but the ph of the RO/DI water is 7 and I don't want to change the water parameters too quickly and cause any problems (my ammonia as well as nitrites have been stabalized at exactly 0 for 3 weeks now)...I'll keep in touch. Thanks again!