Serious Reefs Light Testing Ideas

Hooz

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I watched the video posted this morning, and I had some thoughts that I figured might ramble on too long for a YouTube comment. I figured I'd just post them here for @Ryan - Serious Reefs and @rtparty to see, and maybe open it up a bit for other "Serious Reefers" to post their thoughts.

Anyway, here are the things that matter to me, in no particular order:

1. Mounting Height and Light Spacing (NANO TANKS TOO!)
2. Shadowing
3. Spectrum
4. (Useable) PAR
5. Price

There is nobody out there testing for optimal mounting height and/or light spacing. With VERY few exceptions, there is no single "optimal mounting height" for any light. You must take into account the area that you're trying to illuminate, light beam angle, etc. In all the groups and on all the forums, I see people say "that light needs to be mounted X inches off the water" without first asking what the dimensions of the tank are. The BRStv AI Prime 16HD review highlighted that concept more than any other video. I think that mounting height is a big deal, and critical for setting someone up for success, probably as much as over/under powering the light. The same goes for spacing multiple lights over a larger tank, but if I was only picking one, it'd be height.

Maybe just do the measuring grid at 6" deep and start raising the light until you get to the 15% spill. Do it on a nano tank for nano lights and a 60 cube for larger form factor lights, then at least people can extrapolate from there based on their own tank size. Spacing multiple lights would be a different animal, and I'm not sure there's a compromise to be had there.

I know that it'd be cumbersome to test every light over 6 different sized tanks (like the 16HD review I mentioned), but I think it'd be worthwhile to add in a nano sized test tank, at least for "nano sized" lights ... maybe anything 100w and under? The 15 gallon cubes seem to be very popular (i.e nice, cheap options from Hello Reef and IM leading the charge), so maybe a 15" cube could fit that niche, in addition to the 60g cube and 120g "standard" sizes. I would test small form factor lights over the nano AND 60 cube, but I don't see much point testing the large form factor lights over the nano.

For shadowing, I think the BRS approach was "good enough". Just an objective, "see it with your own eyes" type thing. Here's the light at its optimal mounting height, and here are the shadows. Short, simple and to the point.

For spectrum, PAR and price, I have all sorts of ideas, but one that sticks with me after the 2.75w per gallon SPS lighting test...

You had the Radion XR30 G6 Pro and the Nicrew HyperReef Gen 2 over the same tank, mounted at the same height. You did a generic tune to 60 watts on the Kill-a-Watt meter, 75% to the blue channels and 25% to the white channels. You didn't call it out in the video, but it jumped out at me that the PAR readings between the two lights were almost identical. Like, within a few PAR. One light/mount combo that costs $1100, that has an app and 8 "sliders", compared to a light that costs $350, comes with a mount, no app and only 4-5 adjustment channels. Power/watt were identical. Spread was identical. If you stopped there, you'd think the lights offered the exact same performance, and you might be right. But do they really?

Maybe just build on that methodology a bit. Don't tune to a spectrum per se, but use a generic approach. Pick an arbitrary target wattage. Maybe one target for "nano class" lights and another for larger form factor lights. Tune blues to 75%, "whites" (with red and green if available) to 25% based on the wattage only. See what kind of PAR you get, see what kind of spread you get, then shoot the spectrum to see how it stacks up. See if that $350 Nicrew really is "the same" performance as that $1100 Radion.

Peak PAR at maximum wattage is cool to brag about but, like you said, almost nobody actually uses their lights like that. Open air testing at a fixed height is useful to see what the light is capable of without any environmental influence. Testing grids in a water filled tank is also useful and approximates (but doesn't truly duplicate) "real world" use, although I'd argue that painting the back of the tank black would be more useful and "real world".

I'm sure I'll think of more to say, but these were my initial thoughts and feedback after watching the video this morning.
 
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Freenow54

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To me all your questions can be answered with a par meter . The height for sure measuring at the top of the aquascape where you would like to place Coral. Bear in mind you don't want water splashing on the light . The same with shadows . They were not standing out for me I made a rough map and put in par values recorded on it. I just bought 2 aqua illumination lights to fill in the gap between my 2 Primes which are not strong enough to give decent Par near the bottom of my 100 which is 22 inches deep . Also if you have lids you have to do this with them on . You lose about 15% with good mesh. I have a Razor which has no app but intensity is measured in percentage , and has 4 channels . It was not thought out . It Happens that it covers my entire width on my40 which is about 26 inches wide 16 deep , and is perfect for my mushrooms which thrive , that being said it depends on what Coral you want . I stated on another post that I saw a large deep Tank at my LFS that was deep blue throughout . The Coral were great looking . They stated a lot of Coral adapt to the given light . I have yet to wrap my head around that . I put black ground cloth taped ( 2 sided to the back of my Tank . It really helps prevent Algae growth. However there still was some so I blocked the light from getting to it from the top , and covered the inside with cut up shoe trays . For you to think about
 

Freenow54

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I forgot . If you want prices go to a site here in Canada ie Canadian dollar called Candy Corals . Pictures , prices , and Care level are posted
 

Ryan - Serious Reefs

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I got some ideas I’ve been working on. Goal is up the game and do this better than ever.

In the past we have tested -> collected data -> interpreted in that order. I believe the next evolution will have specific standards or goals and we will performance test to those goals. We will also provide the all data for those with unique needs or which to deviate.

We know about lighting now that we can decide what good to great performance looks like.
 

Pandaexpress

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So excited for the new videos! They're such high quality content, I sometimes listen to them multiple times and take notes. Thank you for the suggestions, they're truly on point. I like the nanotank suggestion as many people nowadays have smaller size tanks due to living space haha... for the testing I guess just do what 'make sense' to common reefers? no need to generate a thousand data points as if for scientific journal publication or something... (reduce workload for Ryan 😆 )
 

Ryan - Serious Reefs

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So excited for the new videos! They're such high quality content, I sometimes listen to them multiple times and take notes. Thank you for the suggestions, they're truly on point. I like the nanotank suggestion as many people nowadays have smaller size tanks due to living space haha... for the testing I guess just do what 'make sense' to common reefers? no need to generate a thousand data points as if for scientific journal publication or something... (reduce workload for Ryan 😆 )
Thanks,

I’ve been exploring some ideas to shift the conversation away from chasing PAR and toward more meaningful performance characteristics. For a long time, the approach has been to collect as much data as possible and try to interpret it later. The problem is that often leaves reefers to decipher what actually matters on their own.

After decades of reefing, researching, and testing lights, I think we can do better. We can design tests that clearly identify desirable performance traits and make it obvious what you’re actually paying for or overpaying for.

These are the things I’ve been thinking through. Basically, what I’d want to know if I were buying a new light or figuring out how to use one I already own.

At the core, it comes down to two questions:
Does it produce enough PAR for my desired application, and is it a good value?

Coverage Area
It’s common to assume an 18" x 18" and a 24" x 24" tank could use similar lights, but the area jumps from 324 to 576 square inches. That’s a 78% increase, meaning you need roughly 78% more photons to achieve the same PAR. That’s a massive and often overlooked difference. We can use data to make this easy to identify for your application.

Mounting Height
As coverage area increases, the light needs to be raised. Higher mounting heights improve spread and evenness, but PAR drops due to spill into the room. The best lights balance these two factors. I’ve explored this before, but I’d approach it differently now, maybe testing in air and experimenting with tools like the Li-Cor LI-191R line sensor to speed things up.

Intended Use
Once coverage and mounting height are understood, you know if a light fits your intended use and coverage area:
50–150 PAR for LPS
200–300 PAR for SPS
350–600 PAR for razors edge pro applications

Price per PAR
Cost divided by average PAR across the intended coverage area. This becomes the baseline for value and helps identify the most cost-effective options.

Mounting Options
Can you actually mount the light the way you want on your tank?


From there, performance testing shifts to wants rather than needs.

Shadows and Shading

After PAR, shadow reduction is the most important performance factor. This isn’t about how light distributes on a flat grid, but how it behaves in a three-dimensional tank filled with growing coral. I’ve tested this across dozens of lights before, but the next step is both wet and dry testing. Wet shadow testing captures how water and glass redistribute light in typical 12–24" tanks, while dry testing shows how it behalves when the glass isn't near the light, especially in larger systems.

Spectrum
Corals can survive under a narrow spectrum like ~455 nm royal blue, but survival isn’t the goal. We want immediate success, less adaptation, and reduced stress. Matching the natural ratio of near UV, violet, indigo, and blue found in the ocean solves most of the spectrum debate. ATI showed this years ago with Blue Plus. Now it’s about moving on from the "LED slider/chose your own adventure" approach to refining and building on that foundation of proven results.

Control and Apps
This isn’t about how many features there are. It’s about whether the system actually helps you set the light up for success. Most don’t. A few stand out, and those should be recognized. The rest can be noted for niche or novelty features.

Shimmer
Does the tank come alive with natural movement, or does it look flat, chaotic, disco, staticky, or have noticeable color separation?

Noise: Is it dead silent in the room or sound like a vacuum is running?

Efficiency: Average PAR per watt over my desired coverage area is the best measurement of how well the light turns electrify into light as well as how much heat is produced in the process.

Aesthetics
Does it look good over the tank? How many cords are there, and is there a clean way to manage them?

At the end of the day, if you had clear answers to these things, would you know enough to pick the right light the first time? That’s really the goal.

One important note: none of this is meant to help you set PAR in your tank. There are already better, simpler ways to do that. Estimating with a watt meter, renting a PAR meter for $99, or even using the DFC $129 Amazon meters will all get you closer, faster, than trying to interpret a PAR grid.
 

Terence

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This is good - I need to ruminate on some of it for a while. I have to additional things to consider:

I think one thing you mentioned in the video with RT is this idea of efficiency. Meaning what is the spectrum when all LED are set to 100%. This should be close to what we want to end up with - with some variance for lights that are market tuned to lean a bit more white and others that lean a bit more violet-blue. With the SKY this is what we did with our LED choice and power distribution. If you turn all channels 100% you get something very optimized.

Second, when I adjust my lights (and I actually do not think this is a nice to have) , I want to be able to "lock in" my spectrum and then with another slider know that the only thing that changes is the amount of PAR at that exact spectrum. As much as that is possible. And, if you run out of "juice" from one channel, be able to either tell the user that past this point you can no longer keep the spectrum, or "borrow" extra "juice" from an under driven channel.
 

gcarroll

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I only see a few things I would suggest.

-Size of the testing tank
I would prefer to see the testing vessel be 36“ x 24“. Having one dimension be 36 inch will allow larger fixtures to not be crippled by spill over. For instance, when you tested the 24 inch Orphek, a lot of light was lost because the fixture was the same length as the tank. It will also give us a better picture as to who really is the king of spread.

-Spectrum:
All of these lights can give us a spectrum capable of growing coal. Coral don’t have legs, so they’re blessed with the ability to adapt to the light being given to them. I feel the bigger problem is people messing with the sliders constantly never allowing the Coral to settle in and adapt.

-testing the light in a spectrum likely for a reefer to actually use is very important to me. It would be nice if maybe in water testing was done this way and maybe do air testing for max output. That should be easy to add that.
 

Ryan - Serious Reefs

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One thing I missed is measuring or avoiding hot spots.

That can be done with the grid of par measurements. However, one thing I’ve found is most of the lights that perform well in the shadow/shading tests also perform well in even distribution.
 

HighDefAquaria

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I only see a few things I would suggest.

-Size of the testing tank
I would prefer to see the testing vessel be 36“ x 24“. Having one dimension be 36 inch will allow larger fixtures to not be crippled by spill over. For instance, when you tested the 24 inch Orphek, a lot of light was lost because the fixture was the same length as the tank. It will also give us a better picture as to who really is the king of spread.

-Spectrum:
All of these lights can give us a spectrum capable of growing coal. Coral don’t have legs, so they’re blessed with the ability to adapt to the light being given to them. I feel the bigger problem is people messing with the sliders constantly never allowing the Coral to settle in and adapt.

-testing the light in a spectrum likely for a reefer to actually use is very important to me. It would be nice if maybe in water testing was done this way and maybe do air testing for max output. That should be easy to add that.
We’ve discussed spectrum previously, and I would be very interested in seeing the actual performance differences achieved with wider-spectrum lighting. The Maxspect Infinite is one fixture I would particularly like to see evaluated.

I’d also be interested in comparing growth and coloration across several different lighting systems. It would be an extensive and demanding test, but potentially very insightful. I believe Ryan may be the only person who both could and would undertake something like this
 

HighDefAquaria

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One thing I missed is measuring or avoiding hot spots.

That can be done with the grid of par measurements. However, one thing I’ve found is most of the lights that perform well in the shadow/shading tests also perform well in even distribution.
Great topic would be -Are we seeing advancements in light par/quality/blending/spectrum.

Example-
Many people would say the Hydra edge is a downgrade from the Hydra 32/64hd.
 
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Hooz

Hooz

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Great topic would be -Are we seeing advancements in light par/quality/blending/spectrum.

Example-
Many people would say the Hydra edge is a downgrade from the Hydra 32/64hd.

I would argue that the Hydra 26/52HD with @luxdium LED and lens upgrade is the best light AI never made.

They have the broadest, most "complete" blue spectrum on the market... and the whites are nice too.

He and @Lousybreed over at Quanta have been quietly pushing the spectrum improvements for several years now.
 

HighDefAquaria

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Great topic would be -Are we seeing advancements in light par/quality/blending/spectrum.

Example-
Many people would say the Hydra edge is a downgrade from the Hydra 32/64hd.

I would argue that the Hydra 26/52HD with @luxdium LED and lens upgrade is the best light AI never made.

They have the broadest, most "complete" blue spectrum on the market... and the whites are nice too.

He and @Lousybreed over at Quanta have been quietly pushing the spectrum improvements for several years now.
I wish @luxdium would make pucks for the 32/64 but I absolutely agree based on the data he's provided.
 

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