Apogee PAR meter - rough idea?

[Who Dah?]

Hello LED experts,

I've read over and over that the less expensive Apogee PAR meter, such as the ~$350 APG-MQ-200, can't be used to accurately measure LED intensities. (Gotta jump up to the $1,200+ line, I get it!)

But - can it be used for rough ideas comparing various LED tanks?

I.e. if I go to a friend's house using Kessil LEDs, measure say 220 PAR using the 'cheap' $350 meter on their Pink Lemonade Acro, could I then use that value as an approximate comparison to another friend's house who is using Radions G1 or G2 or G3? Or Halos, or a 'black box' brand, etc.?

So if someone is using say a Hydra HD, and I take a measurement of 440 PAR on that person's Pink Lemonade Acro, could I then assume that, "wow, this setup is using a significantly more intense setting than the Kessil tank I measured at 220 earlier!"?

Or does it not work like that? (Even in terms of approximation.)

Thanks,
-Who Dah?

 

[Nano sapiens]

'Rough' perhaps, but that may, or may not, give 'good enough' results. Unless the compared systems are exactly the same (each lighting channel is run at the same intensity, the distance from the water's surface is the same, measurements are taken at the same depth, water clarity is the same, etc., etc.), the PAR readings between tanks will very likely be different.

PAR (Photosynthetically Active Radiation) is the measurement of ALL visible wavelengths between 400 -700 nm. For coral zooxanthellae, PUR (Photosynthetically Useable Radiation) is really what we would want to measure for comparison if we could, around 380 - 550 nm ('red' at 620-700nm is also PUR, but poorly utilized by coral).

The Hydra HD uses different type and spectrum LEDs, in different intensities, etc. than the Kessil. Hypothetically, in this example, the Hydra's PAR reading of 44o PAR *may* include a setting with a lot more 'warmer' colors (greens, yellows, oranges) not used much in photosynthesis, whereas the Kessil at 220 PAR may be set to have very little of these warmer wavelenghts, but just as much Photosynthetically Utilized Radiation (PUR), mostly blues and violets. As a result, the corals may do equally fine in both setups since they are receiving similar PUR intensities, even though the PAR is quite different.

 

[Who Dah?]

Gotcha. Bummer... but gotcha. Ty!

 

[revhtree]

Gotcha. Bummer... but gotcha. Ty!

Who are you and welcome..HA!

 

[Who Dah?]

Who are you and welcome..HA!

:D :D

 

[Scott.h]

I just received my apogee QM 500 a few weeks ago. Just released a few months ago designed with LEDs in mind. And with more accurate blue and red spectrum. Buy once cry once. Imo everyone needs one that plans on having a successful life long reef tank. People will spend hundreds on lights, thousands on corals, and scratch their heads for years. And at the same time fret over their phosphates being a few tenths out of line, but never measure light. I'm glad I have one. My best judgments were pretty far off.

 

[chema]

I just received my apogee QM 500 a few weeks ago. Just released a few months ago designed with LEDs in mind. And with more accurate blue and red spectrum. Buy once cry once. Imo everyone needs one that plans on having a successful life long reef tank. People will spend hundreds on lights, thousands on corals, and scratch their heads for years. And at the same time fret over their phosphates being a few tenths out of line, but never measure light. I'm glad I have one. My best judgments were pretty far off.

Are your measurements very different from the ones obtained with former Apogee models? (the MQ-200, for example)

 

[Scott.h]

Are your measurements very different from the ones obtained with former Apogee models? (the MQ-200, for example)

I'm not sure. I don't have a 200. If I knew someone with one I'd check. I called apogee tech support direct before purchasing and they assured me the 500 was more accurate and made for the LED spectrum curve. That said I've seen comparisons between the 200 and the Li-core. I always thought it was pretty darn close for being almost 3k cheaper. It was definitely the best thing that normal people could afford. If they hadn't just came out with the 500 I'd absolutely own a 200

 

[chema]

. I'm not sure. I don't have a 200, but I called apogee tech support direct and they assured me the 500 was more accurate and made for the LED spectrum curve. That said I've seen comparisons between the 200 and the Li-core. I always thought it was pretty darn close for being almost 3k cheaper. It was definitely the best thing that normal people could afford. If they hadn't just came out with the 500 I'd absolutely own a 200

I would like to buy one. I have the opportunity to buy it in USA and a friend would take it to Spain, but I'm not sure whether it is worth of it to spend the difference between the 200 and the 500. That's why I was asking

 

[Scott.h]

I would like to buy one. I have the opportunity to buy it in USA and a friend would take it to Spain, but I'm not sure whether it is worth of it to spend the difference between the 200 and the 500. That's why I was asking

yeah I'm not sure but with everything going LED I would assume eventually they would make other lights obsolete. if you buy the 500 now you'll probably never have to buy anything else. Or worry about accuracy. That was my reasoning anyway.