Personally, I'm not to fond of that setup.
#1 It doesn't look like you have enough flow over the sheet. There needs to be a constant sheet of water coming off the bottom of it. The lower right corner in the pic looks like there is no water, could be just the pic.
#2 The bubbles from the water returning into the sump are going to reek havoc on the probes in there. Can you relocate the probes to a spot with good flow but no bubbles?
#3 You want to lite the sheet as evenly as possible but not as much at the top edge where the water comes out. Algae will form there quickly and slow the flow down dramatically. Also any light bleed to other areas of the sump are likely to start growing algae on those surfaces, including inside the skimmer. One of the 20W lights I linked earlier can be mounted lower and closer to the sheet, This will lite the sheet more evenly and reduce the bleed around the sump, especially once the algae gets established on it. Because those lights are rated IP 65 or 66 water splashing on them won't hurt or risk shorting them out, you'll just need to wipe in down once and a while. I would also strategically place some pieces of black sheet acrylic to block light from hitting things you don't want algae growing on, like in the skimmer. Those 20w fixtures are $25 to $30 delivered if you're Prime. So we're not talking a lot of money. In the end I think you will be much happier with the results if you get one of these.
https://www.amazon.com/Floodoor-Light-Outdoor-Indoor-Greenhouse/dp/B017SU1TLS/ref=sr_1_9?ie=UTF8&qid=1511375670&sr=8-9&keywords=20w+led+grow+light
And look at that, I found one that is $18 Prime delivered!!!
