Replacing/Adding Sand

:freak: Hey yall, I was wondering how I would go about replacing/adding new sand to a reef tank. I have had the tank for about year or so now and I was just wondering what I would have to do? Also, I have researched some on my own. Some people say that adding new live sand to your tank can cause it to go through another cycle again. I have read that some people recommend you add dry sand to an established reef tank? I would just like to hear some ideas and see which one I should go with. When I do my weekly water change I siphon out from the bottom and my sand is finally getting to the point where it needs to be replaced. I've read some people have the same sand bed for 5+ years. However my sand needs to be siphoned because it usually has algae, or deitrus that doesn't make it look good. I currently have 2 clowns, a cleaner shrimp, frogspawn, zoas, and a green clove polyp. Thanks for the help!





P.S. I cant seem to get rid of a red Hawaiian slime algae from the bottom. Also the sand will turn a greenish color too. So I have to siphon form the bottom when I do water changes.