As I stretch the use of my 6 T5 bulbs to the limit, I have been wondering if I should make the switch to LED. As much as DIY sounds good, it's not me. So I have been looking at the AI Sol Blue. Of course, they sell 48" kits that have 4 units but I think that's overkill. Would 2 units be good for a 75 gallon? I still have yet to try SPS yet but like the option.