PAR results help

[Sphyrna_gal]

Okay, I am new to the whole PAR reader rabbit hole and trying to map out my tanks and plan out future corals. Looking for some help to find out where I am messing up with my par results.

I got a $150 par reader off amazon and was so stoked about it but now I am so confused because my readings are in PPFD but it's in a decimal..I look on the forum and look up PAR for coral types and it's usually a triple digit/non decimal number. I looked up maybe if there is some conversion chat but I can't seem to find a way to get it not to be a decimal? LOL.

there's not a way to change the mode on the reader, its just the ppfd in umol/m2/s
; this is the reader I got: https://a.co/d/hDVoxRN

this is my light LED fixture btw: https://a.co/d/dxm6X9u

thanks!

 

[ISpeakForTheSeas]

Can you post a picture of your PAR reading on the meter and another of how you're measuring it?

 

[Sphyrna_gal]

Can you post a picture of your PAR reading on the meter and another of how you're measuring it?

I just set the sensor on my sand bed to get the pic, but you get the idea and can see the reading.

I used this all around the house to test it out, even tried it outside (its a very sunny day today) and I could not get it to reach a triple digit number so..??

 

[ISpeakForTheSeas]

I just set the sensor on my sand bed to get the pic, but you get the idea and can see the reading.

I used this all around the house to test it out, even tried it outside (its a very sunny day today) and I could not get it to reach a triple digit number so..??

And just to check, does the reading change at all if you push the mode button?

 

[Sphyrna_gal]

And just to check, does the reading change at all if you push the mode button?

No that goes into calibration and an option to log your results

 

[ISpeakForTheSeas]

used this all around the house to test it out, even tried it outside (its a very sunny day today) and I could not get it to reach a triple digit number so..??

Yeah, if the mode doesn't switch anything up, then I'd think there's an issue here. The number doesn't seem too far off for your tank light, but (to my knowledge) you should definitely be registering more PAR outside.


Maybe @telegraham or someone else would know what's going on here.

 

[Sphyrna_gal]

Yeah, if the mode doesn't switch anything up, then I'd think there's an issue here. The number doesn't seem too far off for your tank light, but (to my knowledge) you should definitely be registering more PAR outside.


Maybe @telegraham or someone else would know what's going on here.

right? I was thinking originally okay it is just the larger number, forget the decimal but I have confused myself as you can see. Seems wrong because all my corals are doing really good and growing. So even my par of "70" for where my Montis are that 'should be' at a par of 200-300..

The bright spots from our deck was getting 130.5-145.2s which doesn't seem right either.

 

[oreo54]

The screen may only do 2.1 numbers.
Daylight par at say noon at the equator can get to be around 2000
This is data from Hawaii.

Now as to your outside readings, yea they look odd BUT by any chance was there a "10X" displayed anywhere?
Multiplying what you measured by 10 gives you 1305-1452.
"Possible" numbers on clears sky days.

 

[dschuffert]

You are using a light meter designed for greenhouse lighting measurements. Umol/m2/s is also called PPFD. There are formulas to convert PPFD to PAR; all you have to do is Google them. I believe it will be a pain to use this meter for Marine use. I suggest you return it and get something that simply measures PAR.

 

[ISpeakForTheSeas]

Umol/m2/s is also called PPFD. There are formulas to convert PPFD to PAR;

To clarify this:

-PPFD is Photosynthetic Photon Flux Density

-µmol/m2/s is the measurement of how many micromoles of light are hitting a square meter in a second (it's the standard measurement used for PPFD)

-PAR is Photosynthetically Active Radiation; technically speaking, this isn't a measurement of the light's strength, it's a range of light wavelengths (400-700nm)

-PAR is measured in µmol/m2/s; the number just excludes light with wavelengths outside of the PAR spectrum (so it doesn't count light wavelengths outside of the 400-700nm range)

So, the PPFD number only needs adjusted for PAR if the instrument is measuring both light in the PAR range and light outside of the PAR range. With a PAR meter like the OP has, it should only read light within the PAR range, so it shouldn't need the number adjusted at all.

 

[telegraham]

Okay, I am new to the whole PAR reader rabbit hole and trying to map out my tanks and plan out future corals. Looking for some help to find out where I am messing up with my par results.

I got a $150 par reader off amazon and was so stoked about it but now I am so confused because my readings are in PPFD but it's in a decimal..I look on the forum and look up PAR for coral types and it's usually a triple digit/non decimal number. I looked up maybe if there is some conversion chat but I can't seem to find a way to get it not to be a decimal? LOL.

there's not a way to change the mode on the reader, its just the ppfd in umol/m2/s
; this is the reader I got: https://a.co/d/hDVoxRN

this is my light LED fixture btw: https://a.co/d/dxm6X9u

thanks!

Buy this, send me a pic of the sensor, and send me pics of the meters measuring the same light in the same place. https://a.co/d/eWq8fec After that, we can decide which meter to send back. I have not used the Danoplus, but I have the VBR and several other PAR meters.

That measurement for your light could very well be accurate-ish. If I'm reading the info correctly, that's an 18W light.

There are formulas to convert PPFD to PAR; all you have to do is Google them.

This is inaccurate. I'll simplify @ISpeakForTheSeas's very accurate explanation. PAR is photosynthetic light that exists between 400 and 700 nanometers. PPFD is a measurement of how much of that 400 to 700nm light exists at the time of measurement.

 

[Sphyrna_gal]

You are using a light meter designed for greenhouse lighting measurements. Umol/m2/s is also called PPFD. There are formulas to convert PPFD to PAR; all you have to do is Google them. I believe it will be a pain to use this meter for Marine use. I suggest you return it and get something that simply measures PAR.

I definitely searched the web before even posting this question- there isn't a formula or calculator that I could find.. only PPFD/PAR to lux/lumens or other measurements that isn't what I am looking for. I got this danoplus unit because a few other people on here said they used and liked it *shrug* I thought it was one of those mode/settings issues so I'm not sure how others use their unit

thinking about getting something else to measure PAR but also looking into other lights too..although would be a bummer because I loved that this CURRENT fixture controls my powerheads too LOL

 

[dschuffert]

This is inaccurate. I'll simplify @ISpeakForTheSeas's very accurate explanation. PAR is photosynthetic light that exists between 400 and 700 nanometers. PPFD is a measurement of how much of that 400 to 700nm light exists at the time of measurement.

Good point; you are correct; I stand corrected. I learned something new in this post!

 

[telegraham]

Okay, I am new to the whole PAR reader rabbit hole and trying to map out my tanks and plan out future corals. Looking for some help to find out where I am messing up with my par results.

I got a $150 par reader off amazon and was so stoked about it but now I am so confused because my readings are in PPFD but it's in a decimal..I look on the forum and look up PAR for coral types and it's usually a triple digit/non decimal number. I looked up maybe if there is some conversion chat but I can't seem to find a way to get it not to be a decimal? LOL.

there's not a way to change the mode on the reader, its just the ppfd in umol/m2/s
; this is the reader I got: https://a.co/d/hDVoxRN

this is my light LED fixture btw: https://a.co/d/dxm6X9u

thanks!

It's your light, not the meter. @luxdium performed a comparison.

 

[Sphyrna_gal]

It's your light, not the meter. @luxdium performed a comparison. t

thank you for finding this and sending it! I've come to that conclusion. I am looking into new lights ..UGH, back down another rabbit hole LOL

 

[telegraham]

thank you for finding this and sending it! I've come to that conclusion. I am looking into new lights ..UGH, back down another rabbit hole LOL

That rabbit hole is filled with murky water. Happy to share budget-minded options.

 

[Sphyrna_gal]

That rabbit hole is filled with murky water. Happy to share budget-minded options.

I would love to hear some suggestions on systems! I have a 40B right now with hopes of upgrading in a year or two to at least a 48" tank so a light that could move over to another system would be nice.

 

[wet_rocks_reef]

Wow, funny I just got this same light meter from Amazon. Just cracked it open today and with my lights I am getting readings ranging from 500-200 from the top of my tank down to the bottom at the peak intensity for the day. really liked the price of the meter and took the chance. For lights suggestions would honestly find a used light in good condition and get one more when you upgrade. Ecotech radion, or Kessil would be a great used light.

 

[Sphyrna_gal]

Wow, funny I just got this same light meter from Amazon. Just cracked it open today and with my lights I am getting readings ranging from 500-200 from the top of my tank down to the bottom at the peak intensity for the day. really liked the price of the meter and took the chance. For lights suggestions would honestly find a used light in good condition and get one more when you upgrade. Ecotech radion, or Kessil would be a great used light.

Yeah, I do like the PAR reader too, definitely gonna keep it. I think I just thought my lights were way better than they are so when my highest reading was like 80 ...*sigh* I thought it was broken or I was doing something wrong with everyone else saying they got 200+ readings, haha!

Thanks for these suggestions, I want to find something soonish so this helps give me more direction!