Cloudy tank

Alright guys and gals. I've been trying to get my reef back on track and thought i was doing well but I'm not. I was battling cyano for about a month because I slacked where we had our little girl. So I got some time, cleaned everything pretty well, removed the sand and removed the cyano. Thought all was well but about a week and a half ago my tank got cloudy. It's like a brown cloudy. I changed 10 gallons last week (out of a 30 gallon tank) and it never changed anything. Changed 5 more. Nothing. I've been changing carbon filters every 2 days but that does nothing. And yes I do have a hang on back filter but 90% of the time I have no media in it. It's mainly for flow. Can I make a batch of water, take all the rock out, shake it out really well in a bucket of new water? What would you all do?