Duckhams' 75G Reef Build - Eurobraced/BeanAnimal

[Duckhams]

My actinic settings on Radion XR15PRO's. In person the tank is a brilliant blue with serious pop on the coral colours, the picture doesn't really show how bright and blue it is, but you get the idea. PAR readings are low but acceptable given the color spectrum.

With the UV channel set to 0% the sand bed reading drops from 50 to 10. The other readings stay around the same and drop very little.

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[Bugger]

What program did you use to make the picture.
Wasen't it a pain to change the lens

[Duckhams]

Originally Posted by Bugger

What program did you use to make the picture.
Wasen't it a pain to change the lens

I did it all in Pages on my mac. Changing the lenses took me about 2 minutes on each unit. It's really easy.

[Bugger]

Really you can do that much on pages

[Myka]

Originally Posted by Duckhams

I also took a few readings at 100% on all channels just to see what the difference would be. The Radion XR15PRO's put out a LOT of PAR.

I like Radions best of all the LEDS today, but I can't say that you're getting "a lot of PAR". Imo, a lot of PAR is 550+. Indeed, for a "nano" fixture, it's good bang for the buck.

I'm really happy you posted this though because I've been toying with removing a couple T5s from my roster and sliding in a couple XR15PRO.

Interestingly, the XR15PRO are 85 watts each I believe? So you're using 255 watts. I'm getting about 30% more PAR wih my T5 fixture and I'm using 234 watts. I was thinking I would be gaining PAR if I replaced a couple T5s with Radions, and maybe I would, but it wouldn't be any more efficient. Hmmm...

Edit: I keep thinking this is a 36" tank, but you're covering 48" and I'm covering 36" so that throws my calculations way off. However, my tank is 3" deeper too. Though i think you'd be better off wih 4 instead of 3 ...oh for heck this isn't working analytically...nevermind.

[Duckhams]

A lot of PAR is above the 400 range in my mind too, now that you say it. But I am impressed with the Radion XR15PRO's and the PAR output, especially at 100%, they are powerful little fixture. The addition of a 4th may be necessary as I fill in the tank and things start growing in. I certainly would like to have MORE PAR available, but the real question is, is it needed? My SPS all seem very happy, have good colour, acceptable growth and don't seem short of light. Coral placement is a little more important given there are some lower PAR areas in the back of the tank, but I dont see that as an issue right now. Maybe a T5 or two would bump PAR, growth and colour better than a 4th Radion?

[Duckhams]

Ok Myka, maybe this will help. So here are a couple more readings of 2 x 48" 54w T5's on their own and with my 3 x XR15PRO Radion's.

I expect the T5 readings to be a little better once I have them spilt, front and back but they are pretty close with them both mounted at the back of the tank because the reflectors do most of the work. Anyway, you get a general idea of whats what. You literally just add the PAR of the T5's to the PAR of the Radion's, the increase is pretty straightforward.

With that in mind, I would expect 4 x T5's with the same bulb combo to produce 300 PAR mid-tank and 150-160 PAR on the sand bed. But where the Radion's give you wide variations in PAR numbers throughout the tank based on the lenses used, the T5's provide consistent PAR throughout the whole tank, front to back (only minor changes in PAR).
Adding 2 x retrofit T5's to a couple of Radion fixture's is a cheap way to boost PAR numbers and maximize coverage. Possibly adding improvements to growth and colouration to any SPS that were in lower PAR areas. A T5/LED combo fixture seems to be the fool-proof way to go if you're chasing PAR readings.

I personally love my Radion's and have not yet seen any need to turn the T5's on. Everything seems healthy, growing and colourful and I really like the shimmer in the tank. Though I will run the T5's later in the year for a few months to see if I can actually see a noticeable difference in growth or colouration, just for funzies.


T5's ONLY
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T5's & Radions
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Radions ONLY
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[Duckhams]

PAR READINGS NOTE: I've read on RB and several other forums that the Apogee MQ-200 readings are up to 25% less than actual PAR from LED's given the meter's fixed calibration settings (SUN or ELECTRIC). So all the above readings could be up to 1.25x higher than shown.

[Myka]

Originally Posted by Duckhams

A lot of PAR is above the 400 range in my mind too, now that you say it. But I am impressed with the Radion XR15PRO's and the PAR output, especially at 100%, they are powerful little fixture. The addition of a 4th may be necessary as I fill in the tank and things start growing in. I certainly would like to have MORE PAR available, but the real question is, is it needed? My SPS all seem very happy, have good colour, acceptable growth and don't seem short of light. Coral placement is a little more important given there are some lower PAR areas in the back of the tank, but I dont see that as an issue right now. Maybe a T5 or two would bump PAR, growth and colour better than a 4th Radion?

I have to say I do like the PAR range you're getting with the Radions + (only) 2 T5s regardless of the possible err on the measurements. That range is pretty close to what I'm getting from my 36" ATI 6-bulb dimmable T5 fixture.

Is high PAR needed? Well, that depends. First, not every tank is the same, and for reasons that we as a reefing community don't seem to fully understand, some tanks require more or less PAR to achieve the same thing. My guess is that flow, nutrition in the water column, and parameters have a lot to do with it. There are a lot of variables even in tanks that we think are essentially very similar. Do you need PAR over 400 (or 550) in a mixed reef? That's probably not a good idea because more LPS would be bleached by that amount of light. If you have a dedicated SPS tank then maybe you do "need" that much PAR. I've seen SPS tanks in the 550-700 μmol m-2 s-1 and SPS tanks in the 250-350 μmol m-2 s-1 range that essentially produced the same thing - a beautiful, colorful SPS tank.

I never like to feel like I am being limited by my light fixture though. I'm running my fixture right now only at 100% blues, and 60% whites. For whatever reason (flow? nutrition? parametes? or?), I am not able to increase the intensity of the lighting and achieve better results.

[Duckhams]

I agree with you on the above, lots of variables involved to achieve success. Im currently ramping my intensity up 5% per week and seeing how it goes colour/growth wise. You just have to be willing to put the time in to test things out on your system to see what works best.

My tank parameter stay pretty consistent week in week out:
Alkalinity - 9.9-10.8 dKH
Calcium - 400-440
Magnesium - 1400+
Phosphate - 0.04 (Hanna ULR Phos Checker)
Nitrate - 0

I've also started dosing AcroPower this week, so we'l see how that affects things. Reef Roids and Oyester Feast have been added twice a week for night time feedings for the last couple months with good results. Im really working on getting my Microclados and Granulosa to colour up. Everything else looks awesome already.