What intensity do you run 2x Hydra 26hd on a 40B?

[TheDorkLord]

Hi and thanks for looking,

I am just curious what those of you running a pair of Hydra 26 hds over a 40b have your intensity (and maybe the height and spectrum mix) set to and types of corals you keep? Major kudos if you know some of your par levels!

I am doing a pretty evenly mixed SPS/LPS/Softy reef with my hydras at 14" above the water at 75% on the BRS AB+ settings.

 

[DesertReefT4r]

50% max over time should be plenty. I have 2 32 HDs over a 75g 4ft and have them at about 65%, 250 par mid and top of tank growing acros fast. Hydras put out some power don't think them any lesser than a XR15.

 

[ADAM]

Best thing you can do is rent/borrow a PAR meter made to test LED to take measurements. With some seemingly small variables, like water clarity and surface agitation, your actual PAR can be a good distance away from where you guesstimate.

Other than that I think you could find a decent basis from BRStv video where they tested the “AB+“ clone profile on the AI lights. There was a thread here, on R2R, with the AI settings AB+ videos and discussion that should at least get you a good starting point. There’s other videos were they tested the different lights at different mounting heights that shows different depths along with the PAR spread mapping.

AI says the 26/32 had an effective spread of 24x24 at the 8-10” AWL recommended mounting height. At 14” AWL you some available PAR just by lowering them a bit. A 40b with two of these fixtures shouldnt have any issues with light gaps or dead spots at 8-10” if you’re looking to increase the PAR without having to run the fixture at huger/ full power….

 

[TheDorkLord]

Thanks guys. While I appreciate how readily helpful everyone is, I'm not really asking for advice here. I'm just asking what others are doing with a similar setup. Thank you anyway though!