PAR Meter Rental
- Thread starter MNtadpole
- Start date
@MNtadpole didn’t realize you were local. I’m in Wildwood.
Nope
Yup relatively speaking. I live in O’Fallon, IL close to the boarder of STL.
lvanderbeck
New member
I'm in South City, I have an Apogee 420 that hooks up to you computer that you can borrow if you put down a deposit
Huff, Your location is probably the closest to me (O'Fallon, IL). I'll shoot you a PM.
BeanAnimal
Premium Member
I am going to likely shock people... but you really don't need one. As long as you are using any modern fixture and in the same quantity and general spacing as anybody else, with a reasonable channel balance... you are good. Even then, you will likely grow coral at 50% output or 100% output. Playing around will be far more informative than any number returned by a PAR meter.
actual PPFD numbers are pretty meaningless given the tremendous variance in spectrum between fixtures, let alone adjusting the spectrum on one fixture. Take into account error, differences in meters, etc. And 500, 575, or 483 can't really be differentiated to any degree of meaning other than they all have more spectral power than 351, 299 and 313 ppfd...
The "need" for PAR meters has become almost universal, yet nobody really has any clue what they are measuring or what it means in context to the amount or spectrum of light needed.
actual PPFD numbers are pretty meaningless given the tremendous variance in spectrum between fixtures, let alone adjusting the spectrum on one fixture. Take into account error, differences in meters, etc. And 500, 575, or 483 can't really be differentiated to any degree of meaning other than they all have more spectral power than 351, 299 and 313 ppfd...
The "need" for PAR meters has become almost universal, yet nobody really has any clue what they are measuring or what it means in context to the amount or spectrum of light needed.
BeanAnimal
Premium Member
As much as I like my sunrise and sunset... buy do I miss the DE halides. I kind of even miss the thumb and buzz of them turning on.
Well I have relatively new reef setup and I'm trying to dial in my environment. With all the variables between equipment settings and chemistry, I feel like being able to definitively know and set lighting output settings is an easy step in towards a balanced environment.
My thoughts are that if I can ensure that my settings are placing me in a LPS range, that's good enough for me. Since my eyes aren't PAR tuned, I could be well outside those ranges and upsetting my animals.
BeanAnimal
Premium Member
Your (mainstream) understanding is the point.
There is no "LPS Range" with regard to "PPFD" from a PAR meter because the meter doesn't just measure what the coral can (will) need or use. It measures a very broad swatch of spectrum, where only parts of that spectrum are actually useable by coral (PUR).
Let me make two quick analogies (not perfect, but illustrative).
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All Skittles
Blue
Red
Orange
Green
Yellow
Purple
Pink
Voilet
Blue, Pink and Violet are not relevant, (they have no nutritional value at all) but Red, Orange, Green, Yellow and Purple do have nutritional value for some creatures.
However - Humans can only digest Red Green and Purple. The others (Orange and Yellow) are not useable but because they have nutritional value for some creatures that digest and use them, our "skittle meter" counts them.
Jar 1 contains:
Red 150, Orange 150, Green 50, Yellow 100, Purple 50 - the skittle meter reads 500. You only can use 250.
Jar 2 contains:
Red 175, Orange 50, Green 100, Yellow 50, Purple 125 - the skittle meter reads 500. You can use 400.
So the skittle meter reads the same for both, but there is a tremendous difference in what is actually usable because the skittle meter lacks important information about WHAT skittles.
*******************************
Or another simplified way to think of "PAR" would be like "Calories". A "calorie meter" does not tell you how healthy a diet is because a diet is comprised of Fat, Carbohydrates and Proteins and to that end even subsets of those in different complexities.
So If I am on a 2,000 calorie diet that is split evenly between Carbs, Protein and Fat and you are on a diet that is 2000 calories of just Portein, our health outcomes will be drastically different and the "calorie meter" is mostly useless, as it lacks critical information about WHAT calories.
It is my opinion, based on what is being measured, that PAR meters are mostly misused and misunderstood toys. Sure, they provide a bit more meaningful number than lumens, but not really by much.
Please take a look at the chart below for a real world illustration
You have two EXTREMELY different lamps graphed above. Both put put ~125 PAR. Rest assured, given two identical tanks, one with each lamp growth and pigmentation will be vastly different and on the "edge" one lamp may support health coral and the other will not.
More to digest. That was the SAME rig and SAME meter with as many variables removed as possible. If two random reefers had one of those bulbs each and measured them in situ, with the SAME exact model of meter (sensor and software) the results would certainly differ by 25% (or far more). So one reads ~95 and the other ~123. Add in the fact that two different generations or brands of meters are likely used and the numbers can easily be 50% different... maybe 90 and 180...
I hope that makes some sense. I am not sure what 99.9999% of the people in this hobby gain be taking or comparing "PAR" numbers. They don't really correlate to useable data in most instances.
lvanderbeck
New member
I definitely agree that a PAR isn't the best measure of reef lighting success because of the variables you mentioned above, but I still think they are useful. You can use a template that has been tested time and time again to have success across many different tanks/environments (Like AB+ for example) as your basis for spectrum. Then using your PAR meter, you can copy those PAR readings (to a varying degree of accuracy).
If you're using it for blanket readings, sure, it isn't useful, but it could get you 60-75% of the way there to have similar environments that have been successful in the past. Even at the 50% accuracy that you posted above, I still think it gets you more into the ballpark of having a successful tank than not having it at all, given that spectrum analyzers aren't something that are commercially available.
