Hah, alright. It looks like you are in the middle of a cycle.
Your ammonia is way high at .5, after the tank sits awhile, your ammonia will go down once the bacteria establishes in your tank. Ammonia reading of anything higher than 0 is bad.
Your nitrite is also a little high, a nitrate reading higher than 0.0 is high. It will come down when your cycle finishes.
Those mushrooms are pretty much good as dead in that tank, sorry mate. Add some Amquel as soon as you can. It will "lock up" your ammonia so that it might be less hard on the mushrooms and fish. It's a temp fix.
HOWEVER not all is lost. Your tank has to finish cycling. That protein skimmer that you have looks like a seaclone - get rid of it and update it to something better. I recommend coralife super skimmers (they have one for a 65g which should work perfect for you.) Some people have not had as much success with them, but they are easy to dial in and maintain - I don't know what their problem is.
You need to update your filter too. I would opt for an Emperor 400 dual biowheel filter. It has pre-loaded carbon filters that are relatively inexpensive, and two filter media trays that you can add additional carbon, zeovite, or other media to. A
Additionally, you need a lot more internal water flow for your tank. I recommend getting a couple of hydor Koralia 550s and put one in opposite corners to improve your water flow. Point one across the water line at the top of the water for a gentle flow for gas exchange. The other powerhead should point across the middle of the tank, gently blowing at the live rocks.
That red looking stuff that you have on your sandbed and all over your rocks is called Cyanobacteria. There are several FAQ pages that you should read through about how to get rid of it.