So how do you get by without a PAR reading?

[JBL_91762]

Im trying my local forums to rent a PAR meter and so far no luck. Just wondering how you guys got by without one. My 75 g is narrow and deep vs wide. Im a beginner converting fish only to coral. Main focus for now is Zoa's and a mushroom, pulsing xenia

 

[bluemon]

Never measured PAR once in my 15 years in the hobby. Coral are fine.

Also, I think BRS “lends” one to you for 99 dollars

 

[mfinn]

Im trying my local forums to rent a PAR meter and so far no luck. Just wondering how you guys got by without one. My 75 g is narrow and deep vs wide. Im a beginner converting fish only to coral. Main focus for now is Zoa's and a mushroom, pulsing xenia

Talking with other reefers with the same light as you have can give you an idea what they did. Reef club, Facebook?
Asking the question here on R2R. Name the light, tank size ( dimensions), planned corals.
Do it as a separate question. ( not in this thread.

 

[Johnd651]

Talking with other reefers with the same light as you have can give you an idea what they did. Reef club, Facebook?
Asking the question here on R2R. Name the light, tank size ( dimensions), planned corals.
Do it as a separate question. ( not in this thread.

+1

For example, I posted par on a AI blade at varying depths and intensities. Others do similar, you can either search for the light and see what you find or start a post and people will try to help.

 

[fish farmer]

Observe your corals. Start them all on the bottom and slowly adjust placement or increase output from your lights.

 

[Drewe]

Do it old school like we did 20 years ago. 2.25 watts per gallon for SPS and 1 watt per gallon for LPS. Par meters on Amazon cost ~$120 though.

 

[Johnd651]

Do it old school like we did 20 years ago. 2.25 watts per gallon for SPS and 1 watt per gallon for LPS. Par meters on Amazon cost ~$120 though.

Omg...I haven't seen that in forever. Back when you only had 250w or 400w mh options.

 

[hoffmeyerz]

I watch the tank, specifically the coral and how they are responding. Started the xr15's on my tank around 40-45% and slowly upped the power every few days till I found a nice sweet spot where everything seems to be happy

 

[BeanAnimal]

Im trying my local forums to rent a PAR meter and so far no luck. Just wondering how you guys got by without one. My 75 g is narrow and deep vs wide. Im a beginner converting fish only to coral. Main focus for now is Zoa's and a mushroom, pulsing xenia

There is simply no need for a PAR meter. Use any common fixture and size according to manufacturers guidelines, even at 100% you are not likely going to have too much light. Low light corals deeper and in shade, high light corals higher.

Without getting into details, PAR meters are not nearly as useful as people think they are. The hobby promotes them due to misunderstanding, people feeling they are measuring something important to some arbitrary level of accuracy and imaginary guideline… and simple confirmation bias. Advice that they are must have devices is well meaning, but misguided.

The number on a meter doesn’t matter at all… how a given coral responds does matter. You will quickly start to understand how moving corals around affects their growth. Way too much light becomes obvious as tips burn and way too little light as they wither. There is no magic PAR number, or dare I say “ballpark” for any coral. It depends on spectrum, flow and system biome. The same coral in one tank under 400 ppfd may thrive under a different fixture in a different tank under 200 ppfd.

 

[Drewe]

Do it old school like we did 20 years ago. 2.25 watts per gallon for SPS and 1 watt per gallon for LPS. Par meters on Amazon cost ~$120 though.

Omg...I haven't seen that in forever. Back when you only had 250w or 400w mh options.

Can't say we weren't successful using that method!!

 

[obsessedfishlady]

Before I had PAR meter I would take a picture of the coral, figure out what intensity I “felt” was best and then took a picture of that coral again 3ish weeks later. If the coral seemed happier healthier I knew I was good. If it lost a lot of color/closed up I figured it was probably too strong. Not the most reliable since many factors can affect coral, not just light, but it seemed to work for me.

However I think coral can adjust to almost any (within reason) light and that you should set it at your best guess and never mess with it again if you can. Too many fluctuations and changes can negatively impact your coral.

I eventually caved and got a PAR meter for less than $200 on amazon. Yes you can go 30+ years without one, but it doesn’t make it any less beneficial just because you can get by without it. I’m sure the cheaper ones aren’t as accurate but they’re more accurate than my eye balls lol!

This is the one I use and I like it. Since it’s cheap - I’d still use it with caution and treat it as an estimate. Don’t power your lights TOO high. Always start lower.

 

[Drewe]

Im trying my local forums to rent a PAR meter and so far no luck. Just wondering how you guys got by without one. My 75 g is narrow and deep vs wide. Im a beginner converting fish only to coral. Main focus for now is Zoa's and a mushroom, pulsing xenia

There is simply no need for a PAR meter. Use any common fixture and size according to manufacturers guidelines, even at 100% you are not likely going to have too much light. Low light corals deeper and in shade, high light corals higher.

Without getting into details, PAR meters are not nearly as useful as people think they are. The hobby promotes them due to misunderstanding, people feeling they are measuring something important to some arbitrary level of accuracy and imaginary guideline… and simple confirmation bias. Advice that they are must have devices is well meaning, but misguided.

The number on a meter doesn’t matter at all… how a given coral responds does matter. You will quickly start to understand how moving corals around affects their growth. Way too much light becomes obvious as tips burn and way too little light as they wither. There is no magic PAR number, or dare I say “ballpark” for any coral. It depends on spectrum, flow and system biome. The same coral in one tank under 400 ppfd may thrive under a different fixture in a different tank under 200 ppfd.

This is not great advice. People routinely cook their corals with newer LEDs. Get one of those cheap 90 watt popblooms or whatever and you'll see how it's possible. You'll find 400 par in the center and like 150 par 4 inches to the side on tons of LEDs if they're at an incorrect height and have poor spread.

You might have success without a par meter but telling people that you can crank an LED to 100% and not kill anything is irresponsible.

 

[obsessedfishlady]

Im trying my local forums to rent a PAR meter and so far no luck. Just wondering how you guys got by without one. My 75 g is narrow and deep vs wide. Im a beginner converting fish only to coral. Main focus for now is Zoa's and a mushroom, pulsing xenia

Talking with other reefers with the same light as you have can give you an idea what they did. Reef club, Facebook?
Asking the question here on R2R. Name the light, tank size ( dimensions), planned corals.
Do it as a separate question. ( not in this thread.

This is also a good recommendation as well. Someone with success, a similar sized tank, and the same lights could definitely give you a good estimate. I think if I was just doing mushrooms, zoas ect I wouldn’t bother with a PAR meter. They are very hardy unless you’re buying extremely expensive collectors.

 

[obsessedfishlady]

.

 

[obsessedfishlady]

ignore the dot the only way I could delete my comment. Had an error in the app where it said I was quoted when I wasn’t

 

[56longroof]

There is simply no need for a PAR meter. Use any common fixture and size according to manufacturers guidelines, even at 100% you are not likely going to have too much light. Low light corals deeper and in shade, high light corals higher.

Without getting into details, PAR meters are not nearly as useful as people think they are. The hobby promotes them due to misunderstanding, people feeling they are measuring something important to some arbitrary level of accuracy and imaginary guideline… and simple confirmation bias. Advice that they are must have devices is well meaning, but misguided.

The number on a meter doesn’t matter at all… how a given coral responds does matter. You will quickly start to understand how moving corals around affects their growth. Way too much light becomes obvious as tips burn and way too little light as they wither. There is no magic PAR number, or dare I say “ballpark” for any coral. It depends on spectrum, flow and system biome. The same coral in one tank under 400 ppfd may thrive under a different fixture in a different tank under 200 ppfd.

This is in my opinion the best advice on PAR meters.

 

[BeanAnimal]

Yes you can go 30+ years without one, but it doesn’t make it any less beneficial just because you can get by without it. I’m sure the cheaper ones aren’t as accurate but they’re more accurate than my eye balls lol!

Those are contradictory statements… accurate to what standard?

Does that coral need 200, 271, 183, or 307? If my Apogee meter under ideal conditions reads 200, your budget China meter reads 180, and your neighbor’s reads 210 in the same rig — then add user error: angle, water clarity, depth variance, surface ripples, glass reflection, and fixture spectrum. Now the real readings might be 215, 140, and 250 for the same spot. That’s an absurd margin of error given we don’t even know the actual target to begin with.

If you set aside confirmation bias and the folklore passed around the hobby as gospel, it becomes clear that PAR meters are mostly feel-good tools. In most cases, they don’t deliver actionable data worth relying on and there is not target to adjust to even if they did.

 

[exnisstech]

I find a par meter a useful tool in my kit. Coral thrived but clams died untill I tested par and found out I was starving the clams.

 

[obsessedfishlady]

Those are contradictory statements… accurate to what standard?

Does that coral need 200, 271, 183, or 307? If my Apogee meter under ideal conditions reads 200, your budget China meter reads 180, and your neighbor’s reads 210 in the same rig — then add user error: angle, water clarity, depth variance, surface ripples, glass reflection, and fixture spectrum. Now the real readings might be 215, 140, and 250 for the same spot. That’s an absurd margin of error given we don’t even know the actual target to begin with.

If you set aside confirmation bias and the folklore passed around the hobby as gospel, it becomes clear that PAR meters are mostly feel-good tools. In most cases, they don’t deliver actionable data worth relying on and there is not target to adjust to even if they did.

Those are all still numbers that are within range of each other. I’d only be concerned if one read 50 and the other read 300 in the same spot. If my coral can thrive even with all three of those numbers then it was still a successful reading IMO. Because I know I don’t want it to read 600+ for a zoa. I’d be ok with a reading of 50, 80, and 120 in that spot taken by 3 different meters because I know that zoas can handle any three of those readings based on scientific studies that have been done on the topic. It’s been studied over and over again that PAR does in fact have something to do with coral health.

 

[BeanAnimal]

This is not great advice. People routinely cook their corals with newer LEDs. Get one of those cheap 90 watt popblooms or whatever and you'll see how it's possible.
You'll find 400 par in the center and like 150 par 4 inches to the side on tons of LEDs if they're at an incorrect height and have poor spread.

You are making my point without realizing it. It is not the 400, but rather what spectrum comprises that 400.

200 of the wrong spectrum could burn a coral where 400 of the proper spectrum would allow it to thrive.

PAR and PUR are not interchangeable and we can’t measure PUR, nor do we have a PUR guidebook even if we could.

You might have success without a par meter but telling people that you can crank an LED to 100% and not kill anything is irresponsible.

There was clear context to my statement. Any established fixture will have general sizing guidelines. Follow them and community feedback, and you will be fine. Some China black box with no reliable information? It is not a PAR meter that you need, but rather common sense. You ram the intensity over a period of time and stop when you get a negative impact. It makes no difference what a PAR meter reads.