I've only had it since yesterday but it's Kelvin rating is 5000-6500. Which as far as I have heard and experienced is best for growing macro algae. I think 5700 is technically the best. For the size, price, make quality and the fact that it is amazon fulfilled; I'm sold on it. If anything goes wrong at any point of owning it amazon will make it right. They have nano reef lights too with blues greens and reds. If you go to there website, they also have hang on fans that look awesome. Really small heaters, the whole nine yards.