Why so resistant to getting PAR numbers???

[T-J]

Maybe some of you can help me with something that has been bothering me.

It seems that when someone asks for advice about coral placement, or lighting issues, most of the answers first start with a question: What is your PAR in the tank?

What irks me are the responses that a lot of people have: My lights are at 50%. I have (insert manufacturer here) brand, so my lights are fine. They seem pretty bright. I dunno. I can't afford that. My (insert coral name here) is growing fine. Etc. Etc.

Why is there such a resistance to measuring your lighting in your tank??? We test nitrates, ammonia, phosphate, alk, calc, etc. Why such a wall for PAR?

Too expensive?? Shoot. For $60 you can rent one. Maybe even free if you belong to a local reef club. Or buy a Seneye for a couple hundred. The price of checking your PAR can significantly outweigh the loss of a pricey coral due to a lighting issue.

Be a responsible reefer....check your PAR just like all the other parameters your check.

 

[cshouston]

I agree with your premise. Playing devil’s advocate though, it’s $60 plus a $500 deposit. Some people can’t afford to be out of pocket that much for over a week. If so, how they can afford a reef tank is another question entirely.

 

[ScubaFish802]

I've been tempted to rent from BRS but it's a little scary to put up the ~$550 and have something happen, with my luck lol. Or with shipping these days if it is damaged in anyway, it just seems like it could be a risk to me. I am very tempted though. If anyone in VT or surrounding states has one that would be willing to meet in person and or rent one out I would be willing to pay rental $.

For a "one time use" or very limited time use item I can't see myself buying one right now at least..

There's so much online right now and so many people with the same tank that I can at least get a close idea from research around what par I have at "x" depth in the tank etc . .

 

[cshouston]

Yeah, I wish more LFS carried PAR meters for customers to rent for a day. Mine has been talking about the possibility for months, but haven’t done it. Also, VT represent. I lived in South Burlington for a couple of years when I worked at the university of Vermont medical center. I miss it so much.

 

[T-J]

I agree with your premise. Playing devil’s advocate though, it’s $60 plus a $500 deposit. Some people can’t afford to be out of pocket that much for over a week. If so, how they can afford a reef tank is another question entirely.

You do know that BRS isn't the only place to rent a PAR meter, right? A quick search shows other places with a smaller deposit. Also, I bet a few of your LFS rent them as well.
I also suggested checking with local reef clubs. I know mine has them for members in good standing...for free!

 

[ScubaFish802]

You do know that BRS isn't the only place to rent a PAR meter, right? A quick search shows other places without a deposit. Also, I bet a few of your LFS rent them as well.

There is only one LFS (with salt) in my state, and only two others I can find within 6 hours in any direction in surrounding states. Unfortunately we are not all so lucky.

I feel overtime you learn your tank either way, but it would be nice to see exact numbers. Although, I don't see knowing your exact par as a sink or swim thing personally,

 

[92Miata]

I agree with your premise. Playing devil’s advocate though, it’s $60 plus a $500 deposit. Some people can’t afford to be out of pocket that much for over a week. If so, how they can afford a reef tank is another question entirely.

Some of us don't want to float $600 for a one time use product. Its an awful lot of risk - and its an awful lot of money to trust a bunch of strangers on the internet with.

And frankly, there are a ton of beautiful reef tanks out there running without having taken par measurements. SPS tend to make it pretty clear via coloration whether or not they're getting enough light.


They're just not needed. Would I like one? Sure - but there are a whole lot of other things waiting in line first.

 

[Reefs and Geeks]

I'm one of those people who has no idea what par my tanks are. Could be 100...250...350? no idea. I get that renting one isn't absurdly pricey, but if I make any changes to the tank that would affect par, even running fresh carbon vs not changing it out, than I'd again not know what my PAR is. Because of that, I'd personally only see value in buying one. But at a few hundred $, I'm just not THAT worried about it. Been reefing for about 7 years and never had a coral bleach or brown out due to a lighting issue. I just go by the oldschool "put it on the sandbed and move it up till it's happy" if that and it's worked well for me.

Having the PAR might be nice for a select few people who would ask that buy frags from me, but I've had maybe 2 people ask me that in the last year, and not knowing the answer certainly didn't stop them from buying. So...I don't really see enough value in knowing the numbers unless I'm frequently buying coral and too lazy to just acclimate them to whatever my lighting is. I'd rather spend the $50 (or couple hundred to buy) on a new tank...actually I just did exactly that! I'm much more excited to have a new tank to add to my collection than to have the ability to read PAR numbers. Just my personal preferance of course. I do understand the allure of being in more control of your tank, but to me PAR is just one more number to measure and chase. All of that said, a friend of mine offered to measure my tanks when he stops over next, so I'm interested to see what he reads. Doubt I'd do anything with the info though.

 

[Nano sapiens]

Besides the cost of buying or renting a PAR meter, depending on the light sources used, one reefer's PAR can be the same as another, but the effects on the coral can be very different. The classic case is when SPS reefers went from MH to LED and found that the 400-500 PAR that they were used to seriously burned their coral under LED. Has to do with PUR (Photosynthetically Usable Radiation), as LEDs typically have more blue light and thus more PUR.

So be careful using someone else's PAR numbers. Confirm that the fixture is the same/similar (produces similar spectrum chart) and know the channel intensities being used (ex: white=25%, blue= 75%, red=5%, etc.). Otherwise, just use the PAR numbers given out as a 'general guide'.

 

[92Miata]

Besides the cost of buying or renting a PAR meter, depending on the light sources used, one reefer's PAR can be the same as another, but the effects on the coral can be very different. The classic case is when SPS reefers went from MH to LED and found that the 400-500 PAR that they were used to seriously burned their coral under LED. Has to do with PUR (Photosynthetically Usable Radiation), as LEDs typically have more blue light and thus more PUR.

So be careful using someone else's PAR numbers. Confirm that the fixture is the same/similar (produces similar spectrum chart) and know the channel intensities being used (ex: white=25%, blue= 75%, red=5%, etc.).

In addition to this - there aren't really any good reference sources for individual corals - we get the "Acros somewhere between 250 and 350 with LEDS" sort of statements - but nothing like "PC Rainbow needs 330" - so it ends up being a whole bunch of guesswork and moving things about anyways.

 

[Ippyroy]

PAR is only a small part of the equation. There are many other things like spectrum that also play a part. Also LUX and PUR. The clarity of your water also plays a huge part. If a grows out and shades another one it can affect the PAR. i have never tested my PAR levels and I never plan on it. Place a coral where you think it will do good and watch it. If happy and growing don't change. If unhappy then move. Lights also lose strength over time, which will also affect the PAR. IMHO PAR is a waste of money and time. It is but a tiny part of a successful reef tank. Much like ORP. Knowing the value can help, but neither is a huge factor in success vs failure.

 

[rwreef]

For me it is just not that helpful.
If I were to measure PAR on my tank, I would still need to monitor corals within the PAR value I've been told is acceptable for that coral (if you can find it) I would then need to adjust the light/coral up/down to help the coral find its happy spot. I believe PAR is very subjective and maybe nice to know...but not helpful in the same way, PH, Alk, Calc, etc... Maybe I should also be measuring flow at each coral? However, it is a good conversation and interesting topic.

 

[Jib]

As someone who is new to the hobby, I'm definitely going to rent one before I put corals in. I feel like knowing my lighting better will allow me to make more confident selecitons when it comes to corals and thier placement.

 

[Dana Riddle]

I find it odd that some are willing to spend $1,000 on 'the coral flavor of the month' but a $200 PAR meter is too expensive.

 

[Cell]

The easiest answer is that it's not vital for success. But there are many things that probably contribute. It's not very cost effective to purchase one for personal use, as most hobbyists aren't replacing their lights and/or tanks very often. Look at the average reefers storage area, we already have enough stuff collecting dust. So that means rental, which is more involved than hitting a few buttons on Amazon and having a shipment sent to your doorstep. It also means learning how to use the tool, which is probably intimidating to lots of people who don't like using screwdrivers, much less a photosynthetically active radiation meter. There are no exact optimal PAR value for each species of coral, it's more of a range, so knowing exact PAR value of every inch of the tank isn't necessary provided you have a general idea of what does well where, which most people learn just from moving coral around.

 

[StlSalt]

I find it odd that some are willing to spend $1,000 on 'the coral flavor of the month' but a $200 PAR meter is too expensive.

I'd be a lot more interested in PAR at $200. Which one do you recommend?

 

[chipmunkofdoom2]

It's strange that the only options people ever talk about for measuring par are $50 rentals (with a $550 hold), $200+ Seneyes, or purchasing a $600 PAR Meter outright.

You can get a reasonable PAR estimate with a <$20 lux meter from Ebay or Amazon. This Advanced Aquarist article has more info. Dana Riddle even did an article about how you could get a reasonable PAR estimate from a $9.99 plant sensor from a local hardware store.

There's no denying that you'll probably get the most accurate measurement from a PAR meter or Seneye. Having said that, I'm really surprised that every hobbyist doesn't at least have a PAR estimate, especially when you consider that lux meters cost ~$15.

 

[92Miata]

There's no denying that you'll probably get the most accurate measurement from a PAR meter or Seneye. Having said that, I'm really surprised that every hobbyist doesn't at least have a PAR estimate, especially when you consider that lux meters cost ~$15.

The question is - is that estimate going to be any more accurate than I can get watching BRS's videos where they test the PAR of my light at various heights and positions? Or the threads where Dana has tested a whole bunch of other lights? Etc?

At this point - as long as you're buying a fixture that someone has heard of - you're generally going to have a pretty good spectrum - and "good enough" PAR data is readily available.

It makes a lot of sense if you're cobbling together a DIY solution, or buying newly designed lights - but there's not a whole lot of value in testing a Radion, or Prime/Hydra, or even a chinese black box yourself. Its been done.

 

[T-J]

I'd be a lot more interested in PAR at $200. Which one do you recommend?

Seneye. Gives you PUR as well. BRS did a side by side test with a meter and found they were really close!

 

[SMSREEF]

I'd be a lot more interested in PAR at $200. Which one do you recommend?

Black Friday is coming up.
I got the USB Smart Quantum SQ-420 PAR Sensor - Apogee that plugs into my laptop for $190 last Black Friday