I'm a bit confused on this so maybe someone can help me out. I'm messing around with a meter to measure my lights. Its and Apogee QMSS Quantum Meter PPF. With the small amount of research I've done on the difference between PPF and PAR I think I understand enough for now. PAR measures between 400-700nm and PPF measures everything or something like that but that is not my issue. My reading with a 250 watt DE Phoenix 14K read at the light around 700+ but only a few inches below water it drops to 150 or so. The light is about 12" above the water. Most of the tank reads 50 to 60?
When I see people reporting PAR they are showing much higher numbers like 300 to 500 consistently around their tank. My bulbs are probably 9 mos old but I don't understand how others are getting so much higher numbers unless my readings and their numbers aren't measuring the same thing. I've looked at the Sanjay site and he shows PPFD at levels of 125 or so when the meter is 18" away from the source. What are the numbers that others are reporting that are so much higher?
Most of my corals are fairly happy but my SPS could probably look better. I borrowed the meter to try to find out if my lights are strong enough but confused by my results.
Thanks for any advice.
When I see people reporting PAR they are showing much higher numbers like 300 to 500 consistently around their tank. My bulbs are probably 9 mos old but I don't understand how others are getting so much higher numbers unless my readings and their numbers aren't measuring the same thing. I've looked at the Sanjay site and he shows PPFD at levels of 125 or so when the meter is 18" away from the source. What are the numbers that others are reporting that are so much higher?
Most of my corals are fairly happy but my SPS could probably look better. I borrowed the meter to try to find out if my lights are strong enough but confused by my results.
Thanks for any advice.
