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View Full Version : Reef Breeders Photon 48 PAR Values


chrisfont23
06/26/2015, 07:46 PM
I got tired of guessing so I rented an Apogee PAR meter online. I figure if I am going to invest thousands of dollars, I can spend $20 a week to measure one of the most important elements.

My tank is a standard 90 gallon. Mainly LPS. Lights are roughly 7 1/2 inches off the water. Distance from hammer coral (middle tank) to top is roughly 21 inches. Depth perception plays into this as well as the numbers jumping a bit. Three measurements taken: 37/20, 60/40 and 100/100. 90 degree optics. There is little fluctuation when adjusting the blue (1st) channel. The white (2nd) channel is where all the PAR is. I assume the blue is your PUR. Well, thats what Ron Reefman told me and I believe him. Overall, yes - some discrepancy, but this should give all those ReefBreeders users an idea of the par values they get with the lights.

I hope this helps. Any questions, let me know.

Now onto the results:

dillct
06/26/2015, 08:18 PM
Are you using the stock optics?

chrisfont23
06/26/2015, 08:19 PM
Yes.

DavidinGA
06/26/2015, 08:50 PM
Hmm those are quiet a bit lower numbers all around vs what I have heard these leds can do

Bpb
07/03/2015, 12:32 PM
its also a false assumption that blue isn't part of par. 450 nanometers is absolutely in the photosynthetically active portion of the spectrum, and any failure to get a reading there would be the fault of the meter.

Reef_Breeders
07/12/2015, 09:31 PM
Hmm those are quiet a bit lower numbers all around vs what I have heard these leds can do

They are similar to the numbers we got and listed on the site - the 48s and 24s are fairly spread out in terms of LEDs/square inch, so the par is a bit less intense than say the 16s or 32s, but 250-300 at 24" is more than enough to grow sps, in fact that will likely be too much light w/o acclimation.


In response to a different question:

We also did not account for the apogee reading a bit less in the 450nm range - when compared to our scientific grade spectroradiometer, it was actually very close, so little or no adjustment is needed IME.

ZeeSparrow
08/29/2015, 08:14 AM
Thank you for this post. Much appreciated!