I had an algae problem a couple weeks ago. Did some shock treatments backwashing etc etc. I even replaced the sand. I have a SWG and all is good. Ph is in range and all chems are in the ballpark. I test daily at the moment with a Taylor 2006 test kit. Now my issue is all looks good except the water is not crystal clear. It's not green and I'm sure the dead algae is gone but the water is a deep blue say . You can see the bottom but it's a slight blur on your toes. I don't like to add anything out of the ordinary but I just don't know how to solve this. Any help is appreciated.