Light spread for 300g tank.

[Meista_Flya]

Hey guys I'm in the process of purchasing a planet aquarium mega matrix 310 gallon tank. I will be posting a picture below. In the picture you guys can see that there are 3 seperate sections that are open on the top. I have been trying to do some research about the light spread on the xr30 gen 5 pros but really havnt seen any good info besides the BRS video. I see if you are using 2 lights the lights should be spaced about 22 inches apart from each other. But 3 lights look to be needing to be spaced a little closer then that. BUT I'm thing from what I've been told from my local fish store.... the G5 have about a 30 in spread in light. Which I know I'm not gonna put rock all the way too each end. Nor am I going to put rock on the back or front wall. So if I put 3 in each opening, It logically seems like I will be ok for a mixed reef. I seen in another thread someone having 8 xr15 g5. But I feel that the braces will stop that light output with the placement its in. Since the lights are supposed to be 8 inches from the water line anyways.

Another option I was thing was 3 xr30 g5 and a t5/led hybrid rack. But i havnt found a 96 inch one biggest inhave seen was 61 inches if im not mistaken. I could do 2 shorter ones. But then I wouldn't be able to put an ecotech in the center like I was planning.

Light selection is gonna be the killer decision maker in getting this big of a tank. And the most expensive.

Thank you guys for the help.

 

[ca1ore]

What are the tank dimensions?

 

[Meista_Flya]

96" long. 30" deep. 25" high. Has 3 openings on top. With glass brace across the top with another plastic brace on top the glass. So I'm thinking if there is a 30 inch spread on the light. And i place one in each square that should be plenty of light coverage for a gen 5 pro. If placed length wise ( side to side. Compared from front to back.) Since the gen 5 has 100 leds and a massive footprint compared to the gen 4 or other similar light.

 

[Meista_Flya]

Bump

 

[Aardvark1134]

If you want to stick with radions 8 (2 rows of 4) of the Xr15 would work

 

[Meista_Flya]

If you want to stick with radions 8 (2 rows of 4) of the Xr15 would work

I'm trying to understand why though. From what I've seen the xr30 gen 5 have tons of light spread.

 

[Aardvark1134]

Coverage:

• Maximum Spread: 32" x 32"
• Recommended Spread: 24" x 24"

That means if you use the reccomended they don't cover the full front to back 30 inches of your tank and it would take 4x to cover the length. So you could use 8x of the 30 but that would be crazy expensive. Would be much cheaper to use 8x of the 15

 

[Meista_Flya]

What about using it with a t5/led hybrid unit tho?

 

[14 foot reef]

Everything you need to know right here !!!!!

 

[jda]

What are you going to keep? It matters a lot.

If you want to have a wall-to-wall SPS tank, then you would probably need 10-12 XR30s in two rows to cover that thing. The manufacturers recommendations are complete bunk with this type of demand.

If just keeping some lower light stuff, then you can do a lot less, but need to know the plan and stuff.

Whatever you are doing, find somebody who did what you are trying to do and pay attention. People like to quote manufacturers recommendations or videos from other people and while they mean well, they have no idea what they are talking about most most of the time. Lighting a large tank is VERY hard and doing what you do on a small tank and expecting it to scale does not work out.

For me, a tank this size screams 3x large reflector MH and some LED strips - you cannot get anything more effective, with less wattage and better coverage than this.

If somebody made me use LEDS on a large tank, I would do 2 rows of the 48" Photon V2s for good coverage - 4 units total.

Do yourself a favor and do not listen to what any LED manufacturer says. Most are complete BS.

The glass braces will drop the par a bit... I have a large 24" glass brace on my old Oceanic tank, but the light still gets through there effectively and my acropora do well even if the light is less. Just keep the heart of the light from being directly above those smaller braces and you will be plenty OK.

 

[oreo54]

But I feel that the braces will stop that light output with the placement its in. Since the lights are supposed to be 8 inches from the water line anyways.

Braces only stop it for awhile, depending on the light angles. Yea if the light is "perfectly" perpendicular to the water surfac you would have 2 dark bars in your tank (ignoring the edges)

Plenty of BRS vids on par spread for various LED's at depth. 25" isn't "extremely" deep..
One thing though, equal spacing acrosS the top is not the "perfect" way to evening out Par.
Applies to all light sources.


you need to answer a few questions for yourself like
"am I going to favor the center section over f/b"
"how much PAr in that section do I want"
"what color or color options do I want"
"how much am I willing to spend"
W/ LED's one can easily over buy ($$$$) and not suffer due to ease of dim-ability.

Heck 12 AI Primes get you 720W of efficient lighting at the cost of $2500..
Price out 3 250W MH's and a few "glamour" LED strips..

NOT a recommendation, not my forte, just a way of looking at things..

 

[oreo54]

 

[Meista_Flya]

Yea i have looked at all of these. Everyone still has their own methods on what lights they chose and why. Which still all makes ( which is in my opinion the hardest decision) finding the right lights so difficult.

 

[Bpb]

Not sure if it’s been mentioned but you won’t find a prefab 90”+ t5 hybrid unit. T5 bulbs come in a max 60” 80 watt size. If you want bigger like you said you need to double up on smaller ones

 

[jman930]

I used 2x48” aquatic life t5 hybrids over my PA310

 

[jda]

I know that it seems hard, but you will find that nearly everybody that actually solves these problems in real life does it more similar than different. Two rows of LED, or larger reflectors. A few only light a smaller area and keep corals just under the lights forsaking the rest of the tank to open water swimming space - this is a cool look if you have the discipline not to want to fill those areas with corals.

Again, figure out what you want to do with the tank and look at the people who did it and had success - not just a new build. The dude in the video has a nice typical mixed reef with 2 lights for every 2 feet - you could copy this, but with your 8 foot tank, that is 8 of the larger fixtures. Once you dig in a bit, you can easily see why what EcoTech, AI or Kessil recommend does not work.

If you tune out people who are guessing as to what to do, then you will get farther.

Here is another 8 foot tank (deeper than yours which is a big deal) with 10x Radions. He solved this problem and is very open about what he did:

Dr. Joshi’s 500 Gallon SPS dominated mixed reef

Dr. Joshi’s 500 Gallon SPS dominated mixed reef. If you are a reef hobbyist, chances are that you are familiar with the legendary Dr. Joshi. Featured by almost, if not every, reef-keeping print publication, online blog and forum for his coral...

www.reef2reef.com

 

[oreo54]

I know that it seems hard, but you will find that nearly everybody that actually solves these problems in real life does it more similar than different. Two rows of LED, or larger reflectors. A few only light a smaller area and keep corals just under the lights forsaking the rest of the tank to open water swimming space - this is a cool look if you have the discipline not to want to fill those areas with corals.

Again, figure out what you want to do with the tank and look at the people who did it and had success - not just a new build. The dude in the video has a nice typical mixed reef with 2 lights for every 2 feet - you could copy this, but with your 8 foot tank, that is 8 of the larger fixtures. Once you dig in a bit, you can easily see why what EcoTech, AI or Kessil recommend does not work.

If you tune out people who are guessing as to what to do, then you will get farther.

Here is another 8 foot tank (deeper than yours which is a big deal) with 10x Radions. He solved this problem and is very open about what he did:

Dr. Joshi’s 500 Gallon SPS dominated mixed reef

Dr. Joshi’s 500 Gallon SPS dominated mixed reef. If you are a reef hobbyist, chances are that you are familiar with the legendary Dr. Joshi. Featured by almost, if not every, reef-keeping print publication, online blog and forum for his coral...

www.reef2reef.com

hmm.. Seems like Joshi sort of had to "guess" as to his setup..
Light delivery is simple physics..

 

[jda]

Everybody should ask Oreo how he lights his tanks. I do not like to feed the trolls (and make no mistake that he is 100% a troll), but calling out another actually successful reefer who has accomplished something is going too far even for a troll.

 

[oreo54]

Everyone still has their own methods on what lights they chose and why.

Exactly................

Cheapest thing would be 6 Viparspectras @ about 110 real watts each..$600...

You need to decide your needs and find someone w/ a like vision..

 

[Meista_Flya]

im just thinking logically here....... if i have a tank that is 30 inches deep and 96 inches long. and 1 radion xr30 gen 5 pro has 24 - 32 inches of spread..... as per BRS 8 inches off the water........ You can fill up that whole tank from front to back and you can fill up 90 inches of light from side to side. BRS even stated that the xr30 should be placed at "least" 22 inches away from each other to prevent hotspots and have an even par. so if im not mistaken and my math is correct 3 XR30 g3n 5 pros should suffice for a mixed reef tank. I am not planning of filling the whole back wall with rock and corals. im not planning to put rock against the back wall or the side walls. the rock and coral is gonna be centered in the tank with room behind the rocks for fish to swim and fish in front and side as well. at least till that starts getting filled up or i decide to go full SPS from wall to wall then at that point i would get more lights.