Ok gonna try and cover it all here.
55g with sand substrate. Use RO
water from machines at store. Have live rock and a sump. Also a useless seaclone protein skimmer. One power head mounted on left side of tank. Diatom out break is on right side of tank. Currently no fish but a few snails left out of the 20 or so I had in it I think.
Have a test kit but since I just did water Change should I wait till tomorrow to test or would doing it now still be accurate.
On another note read to get rid of green hair algae to use a new tooth brush. Good or bad idea?