I look at lighting first for algae. With those lights, can you do a ramp up and ramp down, and control the color mix and peak levels?
I use three lights for three short cycles (one light per cycle, moving across the tank), and I found that I could do mellow ramp ups and ramp downs, but I could only get away with one hour max for each light, and my max was 50%, with just 10% blue. I also raised my light, so that the contrast between surface light and bottom light was not as extreme.
I really liked the look of the low lights, and I could good color at maybe 20-25% power (probably 03% blue at that point), but growth was more targeted, and as plants came closer to the surface, they suffered more algae issues. I had to tell myself that I would have to deal with having the lighting in my line of sight for a healthier ecosystem. Now my lights are probably about six inches above the water level. I just embrace the room shadows and backlighting to get full coverage.
Since I got an Apex, I have been watching my pH and Temp change throughout the day. I don't have any conclusions yet, because I am not actually practicing science. I think all I can say is that night cycle seems to drop the pH the most, light raises it, and each siesta has a smaller drop in pH. The sunrise-light side of the tank seems to be showing more growth.
I sometimes see an inverse correlation between pH and Temp, but not always. This is with no heater.