By chance I recently had PAR meter #1, and now have #2. Was able to measure the same spots in my tank with the same light settings for a good comparison.
#1 is the Apogee MQ-200 PAR meter. Been our standard workhorse since 2013. Not specifically for in-tank use, so you need to multiply values by the 1.08 correction factor to get the PAR underwater.
#2 is the Apogee MQ-510 PAR meter, new, the main difference is more inclusive reading in the bluer spectrum that is popular now, and it is specific to underwater use so the correction factor is built-in.
The queue has been quite short for #1 now that #2 has been out. I thought I’d share my findings for those of you not sure which to use.
Using both, I definitely get the feel that they are reliable and consistent in their readings. Both now have a nice carrying case and long handle. The readout part is almost the same.
I recently posted my PAR numbers from #1 in my tank journal, before the 1.08 CF. I measured each spot again with #2, and compared the readings with #1 (with CF). One thing to caution is that although these meters give you an exact number, extreme accuracy isn’t the goal here, it is ballpark measurement. Even with that in mind, you will be surprised by the numbers overall and in certain areas of your tank if you haven’t ever checked. Light reflected from inside our tank to our eyes isn’t a good correlation with PAR meter readings at all.
My whitest setting is midday, 75% color setting and 80% intensity in Kessil lingo. At this setting, the #1 vs #2 readings were very consistent, essentially the same accounting for how they jump around a bit even with nearly-still water surface.
Testing a much bluer setting that I also use during the day, 40% color and 80% intensity, #1 was definitely measuring less PAR than #2, as expected due to sensor limitation. I didn’t meticulously do the math, but #1 was around 15-25% less or so, significant. When I went even bluer to 15% and 0% color which I use early morning and late evening, the numbers were less consistent and really significantly under-measuring with #1.
I also noticed that #2 readings didn’t drop off much as I went bluer with the same intensity, which is helpful to know. For example, if you normally run bluer you can check with same intensity but whiter for a more accurate reading with #1.
So my takeaway is that if a relatively whiter setting is part of your high-intensity period, then both meters will give you good results and #1 is probably easier to get your hands on quickly. If you run blue but can adjust whiter for measurement at the same intensity, then either would be good. If you run bluer all day and want to check that directly, you should wait for #2.
#1 is the Apogee MQ-200 PAR meter. Been our standard workhorse since 2013. Not specifically for in-tank use, so you need to multiply values by the 1.08 correction factor to get the PAR underwater.
#2 is the Apogee MQ-510 PAR meter, new, the main difference is more inclusive reading in the bluer spectrum that is popular now, and it is specific to underwater use so the correction factor is built-in.
The queue has been quite short for #1 now that #2 has been out. I thought I’d share my findings for those of you not sure which to use.
Using both, I definitely get the feel that they are reliable and consistent in their readings. Both now have a nice carrying case and long handle. The readout part is almost the same.
I recently posted my PAR numbers from #1 in my tank journal, before the 1.08 CF. I measured each spot again with #2, and compared the readings with #1 (with CF). One thing to caution is that although these meters give you an exact number, extreme accuracy isn’t the goal here, it is ballpark measurement. Even with that in mind, you will be surprised by the numbers overall and in certain areas of your tank if you haven’t ever checked. Light reflected from inside our tank to our eyes isn’t a good correlation with PAR meter readings at all.
My whitest setting is midday, 75% color setting and 80% intensity in Kessil lingo. At this setting, the #1 vs #2 readings were very consistent, essentially the same accounting for how they jump around a bit even with nearly-still water surface.
Testing a much bluer setting that I also use during the day, 40% color and 80% intensity, #1 was definitely measuring less PAR than #2, as expected due to sensor limitation. I didn’t meticulously do the math, but #1 was around 15-25% less or so, significant. When I went even bluer to 15% and 0% color which I use early morning and late evening, the numbers were less consistent and really significantly under-measuring with #1.
I also noticed that #2 readings didn’t drop off much as I went bluer with the same intensity, which is helpful to know. For example, if you normally run bluer you can check with same intensity but whiter for a more accurate reading with #1.
So my takeaway is that if a relatively whiter setting is part of your high-intensity period, then both meters will give you good results and #1 is probably easier to get your hands on quickly. If you run blue but can adjust whiter for measurement at the same intensity, then either would be good. If you run bluer all day and want to check that directly, you should wait for #2.