Should I rent a PAR meter for first tank setup

[puddleglum]

Hi all,

I am setting up my first reef tank.

I am thinking I could "rent" a PAR meter from BRS, or see if anyone local to me has one I could borrow. I could get readings at the bottom of the tank at various points of the tank, as well as at 4", 8", and 12" up from the bottom, and at a few setting of brightness on the Kessil. I do CAD for a living so I can make a few drawings with these values so I have idea of what I am working with at the various locations of the tank, at various depths, and have some idea how adjusting the brightness of the Kessil will affect things.

I am certain, of course, that I don't need to do this, and I probably can find decent settings that will work by a little trial and error and probably only irritate a few corals, so long as I pay attention to their tells. This is my first tank, though, and I was thinking that, if I have PAR values, it might give me a good idea of starting settings on the lighting, and have a good idea of where corals will likely do well. I also could report much more useful information on lighting here on the forum when I am asking questions.

How valuable do those of you who have PAR readings find them?

Any grumpy salty old dogs who want to badmouth all the kids nowadays with their darn-fangled whiz bang dohickeys that should just spend their time and money on salt and water changes? I am equally interested in reasonings why it would or wouldn't be a good use of my time and money.

Thank you,
-pg

 

[Bj’s Reef]

I would rent the par meter. That way you set it up right from the beginning. It removes the guess work setting you up for a better chance of success.

 

[Formulator]

Yes absolutely! Check your local LFS first as they usually do rent them out and then you don’t have to float $500 with BRS for several weeks to account for back/forth shipping.

I refer back to my PAR map almost every time I add a new coral to the tank. It makes placement much more intuitive and you never have to worry about that variable if you have any issues with coral health. You can cross light off the list and move on to other potential causes.

 

[BeanAnimal]

I personally think it is a waste of time and money. The actual numbers are pretty meaningless. It can help with fixture height in context to light balance and hot spots, but most fixtures do just fine 6” to 10” above the water, higher if you have a larger tank footprint with smaller lights.

This hobby is obsessed with an instrument that is misunderstood and misused by the vast majority of people who think it is helping them in some fashion or another.

 

[RWReefer]

I found benefit in it with a new tank and newbie just to get a general idea of light strength throughout the tank. It came in clutch when I identified that the bottom front of my tank was throwing PAR values that were almost the same as the top of my aquascape. Had to get the narrow lense for the radions to fix the issue, but saved me a lot of potential future frustration with low tank corals in what I would have assumed was a low PAR environment that was actually much higher.

@14 foot reef might be able to help you out.

 

[Formulator]

I personally think it is a waste of time and money. The actual numbers are pretty meaningless. It can help with fixture height in context to light balance and hot spots, but most fixtures do just fine 6” to 10” above the water, higher if you have a larger tank footprint with smaller lights.

This hobby is obsessed with an instrument that is misunderstood and misused by the vast majority of people who think it is helping them in some fashion or another.

That’s a hot take. Can you expand upon why you think it is misunderstood or misused? I can’t imagine not having my PAR map in my tank which has a range of about 100 to 800 PAR depending on depth, position (directly under a bulb vs to the edge) and shading of various ledges caves. There is no way to guess in a range that big and expect to have success with a well stocked mixed reef.

 

[805Reefing]

Hi all,

I am setting up my first reef tank.

I am thinking I could "rent" a PAR meter from BRS, or see if anyone local to me has one I could borrow. I could get readings at the bottom of the tank at various points of the tank, as well as at 4", 8", and 12" up from the bottom, and at a few setting of brightness on the Kessil. I do CAD for a living so I can make a few drawings with these values so I have idea of what I am working with at the various locations of the tank, at various depths, and have some idea how adjusting the brightness of the Kessil will affect things.

I am certain, of course, that I don't need to do this, and I probably can find decent settings that will work by a little trial and error and probably only irritate a few corals, so long as I pay attention to their tells. This is my first tank, though, and I was thinking that, if I have PAR values, it might give me a good idea of starting settings on the lighting, and have a good idea of where corals will likely do well. I also could report much more useful information on lighting here on the forum when I am asking questions.

How valuable do those of you who have PAR readings find them?

Any grumpy salty old dogs who want to badmouth all the kids nowadays with their darn-fangled whiz bang dohickeys that should just spend their time and money on salt and water changes? I am equally interested in reasonings why it would or wouldn't be a good use of my time and money.

Thank you,
-pg

Following.. I'm on the same boat. For anyone that has rented one, what would be a fair rental rate for a PAR meter?

 

[redfishbluefish]

Your other inexpensive option is what I call, the poor man's PAR meter.......a LUX meter! You can purchase these for around 15 bucks. HERE is the one I purchased. For LEDs, you want a peak LUX of around 20 - 25 thousand LUX at the surface...or even a bit higher. Search @saltyfilmfolks ...he is the expert on this and has a number of posts talking about how he came up with the conversion numbers. Unfortunately he's out of the hobby and no longer around. Again, this is for LED fixtures.

 

[Jmcg89]

You can also check out brs videos on whatever light you choose if they have one as well as the manufacturer somtimes give par numbers. I know reefbreeders it was available when I got mine. This can give you a pretty good idea of where you're gonna be at.

 

[805Reefing]

Your other inexpensive option is what I call, the poor man's PAR meter.......a LUX meter! You can purchase these for around 15 bucks. HERE is the one I purchased. For LEDs, you want a peak LUX of around 20 - 25 thousand LUX at the surface...or even a bit higher. Search @saltyfilmfolks ...he is the expert on this and has a number of posts talking about how he came up with the conversion numbers. Unfortunately he's out of the hobby and no longer around. Again, this is for LED fixtures.

Thanks! Another rabbit hole I'm about to delve in to... Sounds like a little math involved to convert lux to PAR . Will start doing some reading.

 

[BeanAnimal]

That’s a hot take. Can you expand upon why you think it is misunderstood or misused? I can’t imagine not having my PAR map in my tank which has a range of about 100 to 800 PAR depending on depth, position (directly under a bulb vs to the edge) and shading of various ledges caves. There is no way to guess in a range that big and expect to have success with a well stocked mixed reef.

Guess at what? That the top of the tank has more light than the bottom or a shady spot under a rock has less light than on top of the rock?

Those numbers really mean very little because they are the total energy in a broad swath of spectrum. Two different spectrums with “300” PPFD are not the same with regard to suitability for coral growth or health. Is 300 calories of protein the same as 300 calories of carbs with regard to your health, coloration, or growth?

What is 431 PPFD or 397 or 523? The guy next door has different lights and for that matter a different meter. The numbers can’t be compared. They are rather meaningless. What are you referencing with those numbers? The coral didn’t come with a manual, the values are nowhere near what would be measured under real sunshine on a reef, etc.

You don’t need a PAR meter to know that the light at the bottom of a 24 inch deep tank with a single gen1 radion is dimmer than the same tank with 2 new reefi unos…

PAR meters are a waste of money for the vast majority of people who think they are deriving some value from them.

 

[Cichlid Dad]

That’s a hot take. Can you expand upon why you think it is misunderstood or misused? I can’t imagine not having my PAR map in my tank which has a range of about 100 to 800 PAR depending on depth, position (directly under a bulb vs to the edge) and shading of various ledges caves. There is no way to guess in a range that big and expect to have success with a well stocked mixed reef.

I have a par meter and the only thing it did was let me know what the par was in the tank. Didn't change anything, coral are still growing in the same place, and the same rate. An online search gave me the information I needed to ballpark where I needed to place my coral before I had a meter. The only thing different is I can now tell people what my par level is.

 

[Ziggy17]

It’s helpful for for those that are new to the hobby. It can give you an idea what the values are low, mid and high. I was surprised when I metered my tank with how much lower the PAR actually was compared to what I thought they were. As a result, I increased the light intensity and my corals are way happier. But I guess for some that was meaningless, but it helped me. I guess we all have different journeys in this hobby.

 

[BeanAnimal]

The only thing different is I can now tell people what my par level is.

The disconnect is that the number really doesn’t say much about the quality of light or how accurate the reading was even if it did.

It is like putting a meter on your driveshaft and telling somebody how many RPMs it spins at…. Without gear ratio or tire diameter, the number really means very little.

It’s helpful for for those that are new to the hobby. It can give you an idea what the values are low, mid and high

Low, mid or high compared to what? The last thing anybody new to the hobby needs is to worry about some random PAR number. Top of tank high energy, bottom lower, shadows even lower.

Some people measure 400 at the surface, and some people 800…. Both have wonderful coral and growth. What is “low” or “high”??

. I was surprised when I metered my tank with how much lower the PAR actually was compared to what I thought they were.

Compared to what?

But I guess for some that was meaningless, but it helped me. I guess we all have different journeys in this hobby.

Your corals did better with more light, in most case they usually do outside of extremes… but again, the PAR meter really doesn’t tell you that because it does not take into account the suitability of the spectrum. Your windex blue 400 PPFD and my crisp white 400 PPFD are nowhere near the same with regard to coral growth or health or coloration. The number is meaningless.

 

[Formulator]

Well, I liked my bubble of ignorance better, so I’m just gonna continue using my PAR map. It gives me the warm fuzzies

 

[PharmrJohn]

Well, I liked my bubble of ignorance better, so I’m just gonna continue using my PAR map. It gives me the warm fuzzies

I'm with ya man. I like warm fuzzies!

 

[TangerineSpeedo]

I bought my Par meter used off of Ebay. I think if you are going to measure Par, you should be able to do it on a consistent basis. Because guess what, the Par in your tank changes with coral growth. It's nice you get a general idea when you set your tank up where your par is at, but it does change. For example; I recently set up a new frag tank with the same light settings as my main tank. It seemed slightly brighter, I took out the par meter and yes it was, by at least double. I would have blown my corals out of the water.
The higher Par you have, the more water movement and nutrients you will need.
PAR is photosynthetic active radiation. PAR light is the wavelengths of light within the visible range of 400 to 700 nanometers (nm) which drive photosynthesis
Using a Par meter once will give you a general idea of your tank, using one often will tell you what is going on with your tank in the present. Think of it like an ICP or DOC test. you do not do it every week, but once in a while it's good to see what's going on.

 

[Tamberav]

A par meter is useful to let you know the $600 light you just bought sucks and you need to buy another one $$$ cha Ching!

 

[TangerineSpeedo]

A par meter is useful to let you know the $600 light you just bought sucks and you need to buy another one $$$ cha Ching!

Yes a Par meter will tell you that Primes are really good for a NPS tank or Acans...

 

[BeanAnimal]

I think if you are going to measure Par, you should be able to do it on a consistent basis. Because guess what, the Par in your tank changes with coral growth.

To what end? just knowing some number under some coral gets lower as it grows and produces more shade? What is the purpose?

For example; I recently set up a new frag tank with the same light settings as my main tank. It seemed slightly brighter, I took out the par meter and yes it was, by at least double. I would have blown my corals out of the water.

Same light, same settings… yes the PAR measurement between the two is relative and can be of use to match things up. Different fixture or settings? Then we are back to less meaningful number. But, this is one area where they can be useful and is a far cry from PAR meters being needed or generally useful gear for most.

PAR is photosynthetic active radiation. PAR light is the wavelengths of light within the visible range of 400 to 700 nanometers (nm) which drive photosynthesis

Correct, a wide range of the visible light spectrum. We can have 10 different lights with 10 different settings, all with the same PPFD readings… some will be good at growing corals and some will be terrible. It just depends on the spectral content and peaks.