Why are lights mounted so high in propagation facilities?

[dandi]

These fixtures are mounted what appears to be feet off the water. Their systems are doing extremely well. Can anyone explain why this is the case. I will have a fish room so the any height of the fixture can be utilized. If this has been discussed before my apologies.
Happy reefing
Dan

 

[KrisReef]

So the employees don't bump their heads when they are reaching into the tanks. It's a real thing. Also, these tanks are usually very shallow so they can get away with higher mounts as the shallow water doesn't deflect as much light from hitting the frags.

Don't ask me what spectrum they are using?

 

[dandi]

I watched a BRS video on lighting and recommended mounting heights.
none of them were more than 12" off the tank most 8".
Given the facilities success this leads me to ponder why.
still dazed and confused lol

 

[KrisReef]

I watched a BRS video on lighting and recommended mounting heights.
none of them were more than 12" off the tank most 8".
Given the facilities success this leads me to ponder why.
still dazed and confused lol

I would like to take a PAR meter to one of these places and measure what they are hitting the corals with. My buddy with a LFS had Kessel's hanging 24-30" above the corals in shallow tanks and everything was happy and growing just fine. I never did measure the PAR but I should have.

 

[Troylee]

More coverage and their tanks are much shallower than ours for the most part… lighting a frag tank vs a display tank is 2 different things

 

[Reefer Matt]

I’m guessing they don’t crank up the par like hobbyists do. Also flow has a lot to do with photosynthesis as well.

 

[dandi]

If you have some time take a look at this lighting video. It is extremely informative. How accurate everything is well that's over my head. Thanks for the input.

 

[PotatoPig]

I would like to take a PAR meter to one of these places and measure what they are hitting the corals with. My buddy with a LFS had Kessel's hanging 24-30" above the corals in shallow tanks and everything was happy and growing just fine. I never did measure the PAR but I should have.

My guess is they run lower PAR than you might expect.

My LFS does some propagation of corals in the centers of their sale tanks and has lights up high, and all their corals always look great - torches, hammers, and so on, along with a separate SPS tank. When I rented out a PAR meter they showed me how it works on their tanks - their LPS and soft corals had around 100 par at the surface and 75 +/- 10 on the corals depending on location in the tanks. I asked about the SPS and these were around 150 PAR at the corals.

Not sure on exact spectrum, but they clearly run UV ramped up a little to get corals to pop.

I mentioned I see a lot of recommendations for a fair bit higher, they said in a lot of home aquariums people do run higher and get a bit faster growth, and many of their corals could be acclimated higher, but for them the bleaching risk was too high especially for short stays and new stock - a little low and growth is slightly slow, way too low and problems become apparent over time and you have a window of a few weeks to note and adjust position. Too high and you have a couple days before you’re looking at livestock loss.

Once home I tested with the PAR meter and dialed back my lights, base of tank from 125-135 down to 65-75, and everything down there (a couple of hammers, an acan, and some Zoas at the other end of the tank) look a lot happier. Only thing struggling is a torch if had under higher PAR and bleached, it’s hanging on and I’m optimistic will make a slow recovery.

 

[Hooz]

Places like that typically run their lights higher because they have people constantly in and out of the tanks. They compensate by running more fixtures. Than from Tidal Gardens has said as much in one of his BRStv guest appearances. They aren't as concerned about cost of fixtures or spilling extra light into the room as someone might be when setting up a tank in their living room.

If you've ever been to WWC, their 1500g lagoon tank is also a perfect example. They run the lights 6-8' above the tank, but there are a LOT of them. There was a BRS video a few years ago where they took a PAR meter to WWC. They run PAR ranges on their tanks in the same "recommended" ranges that we do, they just accomplish it in different ways.

 

[dandi]

Check out this video. Largest frag farm in Australia. Over 100,000 frags. Look how few lights they are using.

 

[trmiv]

A lot of the fixtures there at that farm appear to be Orphek Amazonas 320s. They’re 320 watts each. Plus they’re mostly lighting LPS which don’t need a ton of light to begin with. So they’ve got plenty of light with big spread mounted that high.

 

[rtparty]

Ever tried to work in a tank day in and day out with lights constantly in the way? That’s why they’re mounted high. It really is that simple. No need to overthink this

 

[1ocean]

Hi Dan, I just wanted to share what I am doing on my 300. Please understand that what I am doing should not imply that it is the right way...I drove to WWC and several other places. I saw how high they have their lights and yes some of the reason was because staff has to get into the tanks and other reasons where for what they where building. So when I build my 300 2 years ago, I too was concerned about being able to get into it without having to move lights. So I have 4 Radion Gen 5 xr30 blues 18 inches off the top of the tank. About a year later I got my hands on 3 slightly used Kessil 360x tuna blue and put one in between each Radion. I built, two light bar supports one for each side and I used kitchen cabinet draw sliders so that I can push each bar back 8 inches to give me more room to reach the back of the tank. Right now I have mainly lps and zoa's. When I get a few sps for the top of the tank I will increase the lights output since I still have plenty of light intensity to draw from. Right now running Kessils full blue at 60% and Radions at 1700 kelvin at 20% as my middle of the day more light. Everything is happy...I will try and find a picture for you...I have a top that prevents light from spilling into the room.

 

[PotatoPig]

A lot of the fixtures there at that farm appear to be Orphek Amazonas 320s. They’re 320 watts each. Plus they’re mostly lighting LPS which don’t need a ton of light to begin with. So they’ve got plenty of light with big spread mounted that high.

Although it looks like they’re approx 4 feet on center and are lighting up a strip of tank approx 4 feet wide (eyeballing) so about 20 watts per square foot assuming they’re at max power and not losing light outside the tanks.

I realize watts to par isn’t direct, but that’s probably a fair bit less than a lot of home tanks.

Interesting (IMO) that the flow also seems to be fairly gentle (based on eyeballing coral movements) compared to the flow rates in a lot of home aquariums.

 

[1ocean]

Here is a few picture in the build process

 

[dandi]

I really appreciate input especially from those who have visited various facilities.
I have been in the hobby for over 6 decades on and off. Being out of things for 10 years I am striving to gain insight into how things are done now.

Given the large investments these facilities have in livestock I am sure they have used PAR meters to make their lighting decisions. These facilities are obviously successfully growing corals. Troylee pointed out that their tanks are much shallower than our displays. Trying to evaluate things from every angle.
thanks again to all that have contributed!

 

[oreo54]

Check out this video. Largest frag farm in Australia. Over 100,000 frags. Look how few lights they are using.

The Orpheks can have very narrow lenses and are 320 watts each.

High Quality Aluminum Reflector Cups: 15 / 30 / 60 / 90

At 3ft and 15 degrees an led throws a spot size of 9"

Corals are a couple of inches under water.

And they have greenhouses that use natural sunlight.

So kind of a complicated thing.
Low light to high light areas..depending species needs and "coloring" them up.

 

[jda]

Most of these places have shallow tanks. This is important.

I mostly care acropora and the two best acropora growers that I know under LED both have their panels up high with all channels at/near 100%. A spectrum around 10-14k and lots of output. Interestingly, they both use Photon V2.

BRS makes videos to sell products, not really to help people be successful reefing. There are other videos out there of actually how to reef. I would not trust any BRS video without a lot of verification and stuff. Check out Tim Herman and Adam Dickerson on some of the YouTube reef podcasts if you really want to see how people who grow corals fully indoors do it.

 

[GARRIGA]

Unlike a farm. I’m looking to put lights as close to the water as possible just to keep my hands out. Why the AI Blades very appealing. Old school VHO blanketing with less power needed to deliver need. Otherwise I’d want to save my noggin

 

[dandi]

Hi jda,
Hope you are doing well. I realize that BRS goal is to sell products. The videos are a good starting point.
Will definitely check out the other videos you mentioned above.
As always I appreciate your input.
Regards
Dan