It was on a 20g frag tank. And of course you could dial it down but I put 2 frags under from my dt and torched them in 1 day with the hydra on 50% max. It was a bad idea I'm just gonna put t5 over it to match my dt. I don't feel like messing around to figure it out while killing my nice Sps frags.
i have the same light on my 28gl. My sps seems to be doing fine. i started at 40% and worked my way up to 60% where i'm leaving it now. i have it about 18" above the water. My mushrooms are not doing too well however