PAR readings

[kamloops_reefer]

Looking for opinions on PAR readings - I just tried out our Seneye device that we've had for over a year (only used for a month). When I place the sensor just above the water (about 10" from light source) I'm pulling about 160 PAR on a relatively large DIY led build.

This seems low? Am I mistaken that I should be getting 300-600 PAR at the high points in my tank (in water)?

To compare, I tested the sensor against another LED light I have at a similar distance, and a dual bulb 48" T5 HO fixture at approximately 12" below (not in water) and they were 160-170 PAR