Coverage on a large tank

[jccaclimber]

I've bought several Gen3 Pro (XR30w) Radions in preparation for a display tank 126" long, 34" deep. The sand bed to water surface will be around 27".

I'm planning on keeping SPS in at least the top 3/4 of the tank, LPS and zoas on the bottom. I would like a clam at some point, but am ok with adding dedicated spot lighting for it later.

How many, and what layout do you advise?

[Alex Y EcoTech]

jcc,

For an aquarium that size, I would recommend using 5 XR30wG4 or G4Pro Radions. They will provide you with more then enough light for any species or coral/invert.

[jccaclimber]

Alex,
Does this recommendation change significantly for Gen3pro units? I'm sure the Gen4 units are better, but I have 12 Gen3pro units I would like to make use of.

[Alex Y EcoTech]

Alex,
Does this recommendation change significantly for Gen3pro units? I'm sure the Gen4 units are better, but I have 12 Gen3pro units I would like to make use of.

A G4/Pro will provide a wider coverage area and more light. Since you already have the G3 Pros, 5 will likely give you all the light you could ever need.

[biecacka]

So five of either unit will suffice?

Corey

[Noddyfish]

jcc,

For an aquarium that size, I would recommend using 5 XR30wG4 or G4Pro Radions. They will provide you with more then enough light for any species or coral/invert.

Why would you recommend 5? I was just told by "Eco Tech that I would only need 3 XR30wG4 Pro's for a 8 foot 300 gallon SPS reef.:confused:

[Noddyfish]

It's 126 inches...got it

[mattgumaer]

Alex,
Does this recommendation change significantly for Gen3pro units? I'm sure the Gen4 units are better, but I have 12 Gen3pro units I would like to make use of.

I would suggest two rows of 6, using all 12 lights (not sure how wide your tank is front to back). If at all possible, I would use a par meter to fine tune the intensity of your lights. You have a much better chance, in my opinion, of getting even lighting with two rows of gen 3 lights. I can't speak to gen four lights as I haven't used them. I would also suggested considering wide angle lenses for the gen 3s but, if you don't have them, you might see how the regular lenses distribute light, again with a par meter if at all possible. If you have the room, I would also consider hanging the lights fairly high above the tank, particularly if not using the wide angle lenses. If you look at the Coral Labs 'white paper', they're running their lights 24 inches above the water line. I would try to duplicate this, if possible, when using the regular lenses.

Matt

[jccaclimber]

Tank is 34 front to back on the outside, so 32.5 on the inside.

I have an Apogee SQ520, so some measuring/tuning will be in order once this is set up.

[mattgumaer]

Tank is 34 front to back on the outside, so 32.5 on the inside.

I have an Apogee SQ520, so some measuring/tuning will be in order once this is set up.

I definitely wouldn't count on one light covering 32.5 inches front to back, at least for the gen 3s (although I would suspect the same is true for the gen 4s). If it were me (which, of course, it is not), I'd be tempted to put up two rows of fixtures leaving enough space so that you can supplement with t-5s, with one row of bulbs in front, one row in back, and two in the middle if you find it necessary.

I ran three gen 2 pros in a line down the center of a 180 for some time and had trouble achieving even lighting, even with the wide angle lenses. Corals under the light pucks would bleach while those farther away at the same depth would wither away from insufficient light. Getting a par meter was a real eye opener regarding some pretty extreme changes in par intensity in areas that appeared to have a similar brightness. I also have the sq-520. The new software has a built in 'check the box' correction for readings taken underwater. Right now I'm running the row of Radions down the middle with two 5 foot t-5s in front and two in back. I've had a much better time with acropora so far with this set up.

Good luck. I'm sure it is possible to light the tank solely with radions, particularly if you have a bunch of them but, they are tricky to dial in correctly. A par meter should be of great help though. It certainly is possible to have zoas, softies, lps and even sps like montis, birds nests, stylophora and pocillopora with fewer Radions but acroporas seem more finicky.


Matt