Ai prime help

[vetteguy53081]

I have 4 16 HD on 4ft 75 gallon tank and I'm not getting enough par for sps

Ive used primes on and off and they are best for smaller tanks and cubes. You likely would be best with Ai Hydra 26 or 32hd

 

[Hooz]

How high are your lights mounted above the water line? How do you have them spaced along the length of the tank? Since you said you're running the 12" flex mounts, I'm going to assume the lights aren't high enough. It may seem counter-intuitive, but sometimes raising the lights will actually increase PAR.

Four Prime 16HDs on a 4' 75g tank should easily get you into SPS ranges if you get them setup correctly. I'd suggest running them about 12" above the water (the rigid mount set to their max height should get you there), and space the outside ones about 7" in from the ends and the middle ones about 17" in from the ends. It may look a bit strange with uneven spacing, but you'll get nice even spread that way.

As for the "turn down the UV thing", I will say this... Keep the lenses clean, keep the fans clean. The lenses WILL melt eventually no matter what you do, but keeping them clean and keeping the light cool (with clean fans) will prolong the time before they do, and AI will send you free replacements if/when you need them. That being said, don't let melted lenses scare you from running the UV channel. That's an important part of the spectrum, especially for SPS.