Radion XR15 Gen 4 Pro PAR Testing Results

[bcarl77]

Hi all:

I wanted to share the results of my experience with using a PAR meter to measure my XR15 Gen 4 Pro results. In order to try to best lay out all of the information that you may find useful, I will break up the information in the following series posts:

1) Tank Overview and Equipment
2) Ecotech Diffusers:
a) Original Assumptions
b) Exhibits/Data
c) Findings/Conclusion
3) PAR Results
a) Original Assumptions and Schedule
b) Exhibits/Data
c) Findings
4) Key Findings and Take aways

As BRS says, information should never be a barrier and I hope to provide you with information from my testing which may be helpful for your tank.

*DISCLAIMER*: These observations and settings have been derived from a living reef aquarium. No rock structure was moved, and water flow was not changed which causes ripples which causes PAR to constantly fluctuate. The estimated mid point PAR was used for each location. PLEASE use a PAR meter to measure your own tank, before trying to mimic my suggested schedule as numerous variable will change PAR from tank to tank.

 

[BighohoReef]

Looking forward to the results!

 

[bcarl77]

1) Tank Overview and Equipment:
Equipment
Tank: Waterbox 135.4 (48inL X 24inW X 22inH)
Lighting: 3 Radion XR15 G4 Pro (with diffusers)
Mount Locations: ~12inches from sides and 12 inches between the center of each module.
Mounts: RMS Mounts (~7inches)
Top: Screen Mesh
Lighting Schedule: @TopShelfAquatics
PAR Meter: Apogee Full Spectrum MQ510

Overview
My tank is a full blown mixed reef, similar to many of yours. SPS on top, LPS in the middle, and zoanthids on the bottom third. I put the diffusers on my lights back in January of 2020 and noticed some changes with my corals and traced down every water parameter you could think of to no avail. My SPS just were not growing at all, and my zoanthid growth had dwindled. Due to COVID, I decided instead of going and buying more coral I wanted to see how my PAR measures stacked up against what I thought they were. Similar to you I read everyone's threads on the intensity level of radions and kept guessing based on what I though they were using some assumptions and the BRS investigates video.

I rented the @Bulk Reef Supply Apogee PAR meter MQ 510 for Full Spectrum lights, cause as they say "the right tool for the right job". I highly encourage you to take advantage of this service, but make sure you are getting the right meter. Many clubs or LFS (such as Topshelf) offer this service as well, but please ensure you are using the appropriate meter.

For my tank I use the same lighting schedule they use at @TopShelfAquatics. They are nice enough to share the farm schedule with you, and as must of you know, they grow coral pretty well....I get majority of my corals from them and try to emulate their lightning in my tank. The only changes I made to there schedule was the intensity and the times for our viewing pleasure.

The goal of this project was to thoroughly explore and document the effect of using diffusers and measure my current PAR levels. Based on the measurements I was then going to create the optimal schedule based on the results and zoning needed for the various corals.

 

[bcarl77]

2a) Ecotech Diffusers:

I placed the Ecotech diffusers on my lights in order to achieve better spectrum blending and reduce the amount of "disco ball effect". The diffusers definitely help achieve that goal. In addition the diffusers reduce the hot spot under the center of the light and reduce the cone effect. When determining my original lighting schedule I applied an approximate 15% par reduction (Based on the BRS investigates video) in all areas and levels of the tank as result.

In order to test the effects of PAR with the diffusers I set my intensity to 50% on the @TopShelfAquatics schedule and measured at 3 different locations: center of tank (brightest), center in front of the arch (along glass), and front left corner. The measurements were taken with and without all diffusers on.

 

[bcarl77]

2b) Diffusers Exhibit:

 

[bcarl77]

2c) Findings Conclusion
When first looking at the diffusers results you might think.... No way this is correct. It's okay I thought the same thing. What you are seeing here is the result of the "cone" effect from using the single puck LEDs as opposed to T5.

Under the center of the light with or without the diffusers there is roughly 30% PAR loss and as you go deeper you lose PAR. As you measure away from the outside of the center of the cone the diffusers reduce the cone effect and creates a better spread which actually results in an reduction of PAR loss ( i.e. between 12 and 18 inches) using the diffusers. If you are outside the hot spot PAR can actually increase the deeper you go as you are able to pick-up additional light from the cone.

As a result the diffusers will reduce PAR overall, however depending on how far off the center you are measuring the total PAR loss will be different and an equal reduction of 15% to total PAR is not an appropriate measurement.

 

[bcarl77]

3a) PAR Results:
In order to determine where my tank was measuring in terms of PAR I created a "grid" layout of the tank in order to measure the PAR at the various locations to effectively create a PAR map.

I was running my Radions on the @TopShelfAquatics schedule at an brightness of 50% which results at intensity of ~33% at the brightest point. I assumed using the BRS investigates video (3 fixture AB+ at 100%) that this would be equivalent to ~100AvgPAR at 18inches, ~110AvgPAR at 12inches and ~200AvgPAR at 6inches. I reduced the PAR by 15% for the diffusers.

 

[bcarl77]

3b) PAR Results-TSA 50%
Note: Black represents an immeasurable PAR due to rock or obstruction.

 

[bcarl77]

After the first round of measurements I noted that my PAR was lower than expected and I have a hotspot in the center of the tank. I was getting under 200 PAR with locations with SPS, in some areas 100 PAR or less with torches, and just hitting 70ish PAR from some zoanthids. In order to increase PAR and minimize the hot spot I increased the intensity of the outside two lights to 85% and the center to only 65%.

3b) Adjusted light PAR

 

[bcarl77]

3c) Findings:
Due to the faulty assumptions used regarding the diffusers and light strength I was under lighting my tank. I have a significant hot spot in the center over the arch due to the overlapping of the cones of each LED. This is actually a great zone for SPS corals even though they are roughly 12inches below the water line. The lack of SPS growth is due to receiving less than 200PAR in all locations. I need to increase the lights to achieve better growth.

 

[bcarl77]

4) Key Takeaways:
If you take away one thing from this thread, RENT a PAR meter! You have no excuse, want that $200 frag, $100 zoanthid, or $500 torch, do yourself a favor and spend the $60-$80 to know YOUR lighting.

We say in this hobby, if you can't test for it don't dose it. Why doesn't the same logic apply for your lights which are arguably far more important.....

I will be very slowing increasing my light using the acclimation feature within the Radions as I need to go from roughly 50% brightness to 85%. I would like to have been able to spread out the lights farther and reduce the hot spot in the center however my custom lid will not allow that.

I hope this thread encourages you to take on a similar project in your tank so we can continue to share success throughout the hobby.

 

[chet31]

Pretty neat. I've wanted to but have put off (for too long) on measuring PAR. Will be doing that soon.

Also, can you share where you got the lighting schedule used at TSA?
Thanks

 

[Pdash]

I have a similar lighting setup and tank. If I were you I would consider spreading your lights out more and increasing intensity. Although, I suppose it depends on just how much you want to focus on acros, and how much light your lps can take. Some of my acros do considerably better at 350-550 PAR (depending on the individual coral of course) in my experience.
I was also initially under lighting my acros, and, with the help of a PAR meter, dramatically increased intensity (100% overall intensity on 4 g4 xr15s on a RSR 350, and even added additional supplemental t5s, since I've done that my growth has exploded.

 

[bcarl77]

I have a similar lighting setup and tank. If I were you I would consider spreading your lights out more and increasing intensity. Although, I suppose it depends on just how much you want to focus on acros, and how much light your lps can take. Some of my acros do considerably better at 350-550 PAR (depending on the individual coral of course) in my experience.
I was also initially under lighting my acros, and, with the help of a PAR meter, dramatically increased intensity (100% overall intensity on 4 g4 xr15s on a RSR 350, and even added additional supplemental t5s, since I've done that my growth has exploded.

Interesting.... I wish I could widen the lights but would need a whole new top and dont really want to do it. If I was doing primarily SPS I would be switching over to XR30s for sure. SPS is not the primary goal and I am just trying to keep some of the easier frags.

How do the lights perform at 100%? I noticed during testing the fans kicked on at about 80-90%.

 

[bcarl77]

Pretty neat. I've wanted to but have put off (for too long) on measuring PAR. Will be doing that soon.

Also, can you share where you got the lighting schedule used at TSA?
Thanks

You can reach out to them directly. I believe they are still using XR30 Gen4 Pros and possibly other supplemental lighting in the farm.

 

[Pdash]

Interesting.... I wish I could widen the lights but would need a whole new top and dont really want to do it. If I was doing primarily SPS I would be switching over to XR30s for sure. SPS is not the primary goal and I am just trying to keep some of the easier frags.

How do the lights perform at 100%? I noticed during testing the fans kicked on at about 80-90%.

Fans definetly run, but the lights have ran without issue.

 

[bcarl77]

One thing to add, the SPS AB+ does run a slightly higher PAR level than the TSA schedule. For comparability I'd reduce the SPS AB+ by roughly 5% to match the PAR levels above.

 

[Res_Ipsa]

Very cool read! Thanks for doing your own testing @bcarl77 and sharing your results!

I was actually in a similar boat and recently rented my local club's Apogee MQ-210 since adding diffusers to my two xr15 G4's last year. I actually just put together a little picture of the par results. I'm in the middle of a 3 week acclimation from 60 to 65% overall intensity and think that'll be where I stop.