Is a Radion XR15 enough for SPS on cube tank

[Dr. Jim]

I have a new Red Sea 170 (24" x 20" x 20"H) with a Radion Gen 4 XR15. (This is my first LED tank after many years of halides). My plan is to have only SPS (acros) (and this tank is really an experimental tank being that my house is up for sale and I need to wait before setting up a larger system). I've always thought that the Radions are generally not run at 100%. But I found that the PAR (measured with a Apogee 210) is nowhere near 250-350 (at 100%, using Echotech's AB+ settings with a little extra Cool White) except a couple of inches below the surface. I removed the diffuser from the light and now I can get the desired 250-350 but no deeper than about 12" and not near the perimeters.

For those of you with expertise using the Radions, does this sound about right? (I don't think I am operating the PAR meter incorrectly, but that possibility crossed my mind).

If this is all the PAR I can get from the G4XR15, I am considering selling it and buying the new G5. (I just bought the G4 right before they announced the G5...just my luck!

Thank you for any input.

 

[AZMSGT]

How high is the light off the water?

 

[chris k.]

I have the xr 15 gen 4 on my deep blue rimless 29 gallon i am running the light on the rms and at 100 percent at 15k. My sps are fine but i keep them closer to the center. This is my frag/grow out tank.

 

[jda]

You are on this... you are not missing anything. The xr15 is not a powerful light compared to where you are coming from. To put it in MH terms, that xr15 is going to be about like a 70w Halide with more shadows. The xr30 is going to be more like a 150 or 175w halide when run at "normal" output levels (not at 100%). As you know, you can run a cube like that with a single 150w or 175w halide, but some like more power and more coverage. A pair of xr15s offers the same power and you can spread them out more for better coverage.

 

[Dr. Jim]

How high is the light off the water?

I am using the Echotech clamp-on mounting bracket so it is about 9" from the water surface.

 

[Dr. Jim]

I have the xr 15 gen 4 on my deep blue rimless 29 gallon i am running the light on the rms and at 100 percent at 15k. My sps are fine but i keep them closer to the center. This is my frag/grow out tank.

Are you using the diffuser?

 

[ca1ore]

XR15 Gen 4 Pro is a fine light, but you’re asking waaay to much of it for 20x20x20.

 

[Dr. Jim]

You are on this... you are not missing anything. The xr15 is not a powerful light compared to where you are coming from. To put it in MH terms, that xr15 is going to be about like a 70w Halide with more shadows. The xr30 is going to be more like a 150 or 175w halide when run at "normal" output levels (not at 100%). As you know, you can run a cube like that with a single 150w or 175w halide, but some like more power and more coverage. A pair of xr15s offers the same power and you can spread them out more for better coverage.

This is sounding a little disappointing. If I was using a halide on my present tank, I would want it to be a 250W. And, I don't think I would want to have to put two XR 15's on a 24 x 20 tank. When I set up my next tank (which will probably be my "dream tank", and final tank after I move), I was planning to use 8 or 10 XR15's on a 6' tank (probably x 36"x30"H). I just read thru the recent thread on halides vs LED's and was surprised to see how many still like halides. I thought I was the rarity! (I use to be a vendor at shows and was the only one to have a halide over my frag tank....but I had great colors and got tons of compliments!) But I will give the Radion a fair chance on my temporary, experimental cube tank (which will eventually become my SPS Q-tank).
I also have to investigate the GHL Mitras, now that I recently bought a GHL Controller system (which I love!)
I did have a Kessil 360 over a 2x2 frag tank for a while, a long time ago. All my corals browned out with it. I thought of it as being equivalent to a 175 halide at best. (The problem may have been that my colonies were grown under halides so maybe I shouldn't have expected great results suddenly putting them under an LED....but i really think the lower output from the Kessil was the culprit).

 

[Dr. Jim]

XR15 Gen 4 Pro is a fine light, but you’re asking waaay to much of it for 20x20x20.

Do you (or anybody) think that if I replaced the G4 with the new G5 I will get what I want on the cube? I think I read that one can expect 20-30% more output with the G5??

 

[Gungo]

Currently have a 24x18x18 tank with aquatic life hybrid and XR15.. SPS not doing well.. Just bought a second XR15 to have the par I am looking for!

 

[Dr. Jim]

Currently have a 24x18x18 tank with aquatic life hybrid and XR15.. SPS not doing well.. Just bought a second XR15 to have the par I am looking for!

I'm sure there are a million possible reasons your SPS aren't doing well.....but I wouldn't assume it is because of your lighting. Could be, but your LED/T5 hybrid sounds pretty nice.
I was just looking at that hybrid tonight! (and the Giesemann hybrid). I was trying to figure out if there is a way of mounting it without hanging it. At first I was wondering if the Aquatic Life could be set on the XR15 "clamp-on" mounting bracket (along with the XR15 of course).....but am guessing it would be too heavy for that. I would think 4 ATI Blue+ bulbs added to the XR15 would probably do the trick. Unless I find a way to add the T5's without hanging from the ceiling, I may be leaning toward replacing the G4 XR15 with the new G5 XR15. (Still hoping someone will comment on this idea....Thank you!)

 

[Dr. Jim]

Currently have a 24x18x18 tank with aquatic life hybrid and XR15.. SPS not doing well.. Just bought a second XR15 to have the par I am looking for!

Oh..sorry...just reread your post. I missed that you just added a second XR15. So I guess your point was that even with the T5's added to the original XR15, you STILL weren't getting enough par. Good to know! Thanks!

 

[Gungo]

Don't worry. It's 100% true when you say that there could be a million reasons but is proven that when you do par testing and you are below 200 that is not the best for SPS. I am 200-ish with the lights at 70-80%. I might get a few hotspots with 300+ par but the thing is that LED's are not made to run at 100% for too long in my experience. What do you prefer, one single fixture running 100% and get a lot less of lifetime or get two running at 50% and enjoy a better spread plus not pushing your lights too hard?

truth is that there will be a lot of opinions. If you're just starting then get one and time will tell if you'll need another one

 

[Dr. Jim]

Don't worry. It's 100% true when you say that there could be a million reasons but is proven that when you do par testing and you are below 200 that is not the best for SPS. I am 200-ish with the lights at 70-80%. I might get a few hotspots with 300+ par but the thing is that LED's are not made to run at 100% for too long in my experience. What do you prefer, one single fixture running 100% and get a lot less of lifetime or get two running at 50% and enjoy a better spread plus not pushing your lights too hard?

truth is that there will be a lot of opinions. If you're just starting then get one and time will tell if you'll need another one

I'm only "starting" with LED's. (Been in the hobby 50+ years; SPS since halides were introduced to the hobby). I agree with you that PAR below 200 is a red flag which is why I am looking to remedy this now, rather than waiting.
But I wasn't aware that running the LED's at 100% will wear them out faster. I certainly don't want to do that. Since I am leaning toward Radions for my next "big" tank, after I sell my house and move, I think I might just get a G5 XR15 now and put it side by side next to the G4 for my temporary cube tank. I'm guessing if I do that, I won't need the T5's. Would you agree?

 

[Gungo]

If you think you will be fine with the color difference go for it. I personally tried G3 with G4 and the difference was soooo noticeable that didn't handle it. Don't know about G5 and G4.

 

[Dr. Jim]

If you think you will be fine with the color difference go for it. I personally tried G3 with G4 and the difference was soooo noticeable that didn't handle it. Don't know about G5 and G4.

Thanks for the warning! I didn't think of that, either, so it will be interesting to see. Since this is a temporary tank, I may not care too much with this tank. Next tank will have all G5's (provided I get positive results from my current "trial"). I may call Echotech and see what they say about this.
Thanks for helping!

 

[ca1ore]

Do you (or anybody) think that if I replaced the G4 with the new G5 I will get what I want on the cube? I think I read that one can expect 20-30% more output with the G5??

Personally cannot say .... no experience with the gen5.

 

[chris k.]

Are you using the diffuser?

No i am not using the diffuser.

 

[AZMSGT]

G4's are a proven light and work. However you might benefit from a better blanket of light than 1 XR15. There are of course several options to increase the spread. I honestly think the 1 light can do the job but it might be a bit on the lite side of things.

1. Add a 24" T5 fixture to the set up. T5 and LED is an awesome combination. Well worth considering

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2. Add a second Gen 4 or a Gen 5 (I'm looking at adding two G5s to my 3 G4s just to run them at 50 or 60% rather than @95%

 

[RCS82]

I have a 24" cube with a G4 XR15 over it plus a 250w halide. The Radion is there for aesthetics only and I would not rely on it for much more. Sure it will light the tank and will be "fine" and "good enough" but my goal is sps dominant and I don't like to skimp.
I love the LEDs and if I were to only have LEDs I would be doing maybe 3 XR15s over my cube or 2 XR30s to match the spread/coverage/output of my halide.