I was gone for 4 days and came back to a cloudy tank. It has apparently been cloudy since I left, father in law was looking over things while I was gone. I did a 10% water change before leaving, and put food in containers for him to feed daily while I was gone. I come back and I have a ton of diatoms on the sand, and everything is orange/brown on the walls of the tank and sump. I have a couple corals looking rough but most are ok. All my levels look fine, and I am thinking it is an algae or bacteria bloom. Algae I thought was usually green and this is milky white. I plan on doing a 20-30% water change today and getting the sand clean but need feedback. Tank has been set up since July, and I run Gfo and mildy dose the tank for additives and trace elements.
Here are a couple pics for reference.
Here are a couple pics for reference.


