Does this look like a tank with a high 50ppm Nitrate problem?
Back glass is covered in algae which for now is not bothering me as it feeds my urchin and there are a couple of tufts algae on the top of my rock.
Sand is clear.
Get a better light and watch phosphates (dose if they get too low). You will be amazed at how well macro algae can work at lowering nitrate and phosphate