Okay, so I made a rookie mistake about six months ago when setting up my saltwater (FOWLR
) tank. All measurable are at 0 and salinity 0.25. Temp 79. Lights (quad t-5's with moonlights) on about 7 hours a day and feed twice a week. Five fish total about 5-7 inches. Two canister filters (one cleaned per week) with a five foot, four inch diameter DIY protein skimmer. 160 lbs of live rock, 150 gallon aquarium. So when starting the tank, I put in a mixture of crushed coral, live sand, and playground sand. I have had diatom, red slime issues from the get-go. From what I've read, the playground sand was a big mistake. My question is, should I remove all of the sand/substrate from my tank? If so, can I add new substrate afterward and what are the recommendations on that?