Great articles on aquarium lighting, with emphasis on PUR.

BobbyV

Established since 2008
A majority of us in this hobby have become coral fanatics.

We go to great lengths to acquire a wide variety of species to enjoy.

We also have a responsibility to prioritize coral health.

Lighting has much influence. My lighting fixture of choice is the ATI 8 x 80w.

Simple & Effective - Great Quality.

Through much research of which bulbs to utilize, I have learned that the ATI Actinic bulb has loads of PUR.

So what is PUR?

"PUR stands for Photosynthetically Useable Radiation. PUR differs from PAR because the basic definition of PAR is any light in a specific frequency range. PUR is the usable portion of PAR, and different photosynthetic species will have a different PUR range to which they respond."

Through this most current article I have found, PAR of course is absolutely important, but what I found that was interesting was the particular researcher's beliefs/findings that PUR is equally if not MORE important.

It was interesting to learn that the researcher had an example of an SPS tank that had lower PAR values but with increased PUR values to compensate. The average PAR reading was 160 and never exceeded 200.

As a result the corals exhibited more vivid deeper color.

This does make you think. If I don't change anything else but increase more PUR values the outcome would be favorable.

So with that said through support of another well know local member, what I believe to be a choice ATI bulb selection are as follows.

Front

  1. Blue Plus
  2. Coral Plus
  3. Actinic
  4. Purple Plus
  5. Aquablue Special
  6. Actinic
  7. Coral Plus
  8. Blue Plus
Back

Please share your thoughts:
 
Interesting reads for sure. I have had many arguments with folks that believe a red or green light on an LED makes it "Full spectrum".
 
White bulbs offer a "full spectrum" as do LEDs. They just don't generally peak at green or red.

blue special, purple plus, coral plus, aqua blue plus, etc... a balanced reef spectrum isnt peaking red or green but has a full range of the colors I.e full spectrum...
 
WIth LED they have a much narrower range of light than a bulb produces. The diodes is designed to produce one color. I am sure they have some variations between brand, power, etc. but for the most part a 450nM blue sure doesnt have much red.

The theory is then add some of every color and you get full spectrum. reds and greens. I have 2 red diodes and about 8 green. Green helps to bring out the orange/red pigments. MY pinkish BTAs have shifted more firey orange with the green added.

Red i just added in the mix cause two prob couldnt hurt or help.

I wish i could find the article where they discussed the process of coral producing color pigment to block certain light waves.
 
so, how does someone increase PUR without increasing PAR?

The researcher referenced quality LED's or Bulbs.

For instance, my ATI Actinics are loaded with PUR. This absolutely helps with my full spectrum offering.

If you are an LED user, you want to only invest in higher quality LED's.

The chinese lower quality LED's apparently do not carry too much PUR.

LED's are great - but through my experience it is MUCH easier to grow anything under a quality ATI T5 Bulbs.
 
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I have to say that I have amazing growth under my 8 T5 Better than when I had (2) 150 Metal with 4 T5

Front

1. Giesemann Lagoon Blue
2. KZ Coral Light Super Blue
3 ATI Blue+
4. ATI AquaBlue Special
5. Blue+
6. Giesemann Lagoon Blue
7. ATI Purple +
8. ATI Blue +

Not sure what PUR is on that or Par but I do have amazing SPS Growth.

Also I am testing some bulbs and I like the Coral On the KZ vs ATI blue+ not sure on the Giesemann yet like the color but 2 might be to much on the green spectrum.
 
If you are an LED user, you want to only invest in higher quality LED's.

The chinese lower quality LED's apparently do not carry too much PUR.

Most actual LEDs are manufactured in Asia.

I think Crees come mostly from Taiwan and Crees are regarded as high quality LEDs (depends on the model I guess). Also some LED fixtures like MaxSpect Razor come with UV/Super Actinic dual-core LEDs.

Comparing T5s to LEDs, T5s lose spectrum over time compared to LEDs which keep spectrum but lose intensity. So in theory those 420/410 Actinic T5 bulbs won't actually hit the photosynthetic peak of 410/420 through their life, they will slowly shift their nm output where LED UV chips should in theory keep a constant nm output which means better overall PUR in the long run.

That's just going by what we know about them - it could he completely bogus in real life application.
 
Most actual LEDs are manufactured in Asia.

I think Crees come mostly from Taiwan and Crees are regarded as high quality LEDs (depends on the model I guess). Also some LED fixtures like MaxSpect Razor come with UV/Super Actinic dual-core LEDs.

Comparing T5s to LEDs, T5s lose spectrum over time compared to LEDs which keep spectrum but lose intensity. So in theory those 420/410 Actinic T5 bulbs won't actually hit the photosynthetic peak of 410/420 through their life, they will slowly shift their nm output where LED UV chips should in theory keep a constant nm output which means better overall PUR in the long run.

That's just going by what we know about them - it could he completely bogus in real life application.

Cree LED chips are made in Durham, NC, I've spent way too much time onsite there. The packaging currently is done in Asia however they are expanding the Durham site with plans to do the packaging there.
 
Most actual LEDs are manufactured in Asia.

I think Crees come mostly from Taiwan and Crees are regarded as high quality LEDs (depends on the model I guess). Also some LED fixtures like MaxSpect Razor come with UV/Super Actinic dual-core LEDs.

Comparing T5s to LEDs, T5s lose spectrum over time compared to LEDs which keep spectrum but lose intensity. So in theory those 420/410 Actinic T5 bulbs won't actually hit the photosynthetic peak of 410/420 through their life, they will slowly shift their nm output where LED UV chips should in theory keep a constant nm output which means better overall PUR in the long run.

That's just going by what we know about them - it could he completely bogus in real life application.

I agree on your commentary.

There are pluses and minuses on both applications.

ATI Bulbs in my opinion are the best manufactured T5 Bulb available.

If you have an intention of replacing them within 12 months of application, I believe you will be satisfied per their performance.

In regards to LED reliability, yes - they are solid without question. I liked LED's.

However ease of use applications with SPS, through my experience T5 has been the most successful for me. I am over the tinkering phase and bleaching new frags.

T5's are an old reliable method. Yes they cost more to run, but to me. It is worth the expense.

I have spent the high dollar on LED and I know there is a learning curve. Congrats on those who have mastered them with SPS.

Thank you for your added thoughts.

Keep them coming.

These best part of this hobby is learning from others whom have the same interests in mind.
 
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