I know this isn't about kessil.... Are you 100% sure it was the lights? Because there are tons of people who can grow coral like mad with kessil. I had explosive growth with mine. Then all of sudden nothing, great color no growth. Turns out it was my alk. If I keep it at 9 coral grows grate. Anyway my lfs I get 99% my coral from just switched to ocean revive from AI. All his coral looks great and it's nice I don't have to light acclimate anymore when I buy coral from under them. He uses them on his 360 gallon farm tank and he gets good growth and great color. He said they arnt MH but the cost he saves in electricity he said it's worth it. Also he says here is guy that lives here who has the best looking tank in the area and he runs them. That's who convinced him to try them. Any way sorry this is so long.