You could be experiencing what we refer to as the uglies in a new tank or there could be other issues. Please contact me at the store or come in and see us. There are a number of questions that we would need to ask about your setup to help figure out what is going on with your tank. It's difficult to do that here on the Google page.
I would just do a partial water change, suck up the sand to clean it With the syphone hose. Clean filters. But, Don't use tap water. Its kills the good bacteria on your filters. I use my well water. Or the distilled i get from op aquatics.
If you go up to Orange Park Aquatics Jason is normally there and would help you out he's very knowledgeable
Get pictures if you have a Facebook join Duval reef keepers or you can go talk to Jason in the store
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