Hybrid light spacing for 6' tank

[amps]

Hey guys! I've got a 180 gallon tank that I'm about to start rebooting. It measures 72" x 24" x 24". The goal is to have it be 75% SPS, 25% LPS.

I've picked up a 48" Aquaticlife hybrid fixture and my plan is to mount 3 XR30 G4 Pro's in it. Now because I didn't opt for the 60" model due to extra cost and electricity usage, I'm stuck figuring out how to space the Radions to get the best coverage without excess hot spots or shadowing. The default mounting option is to stick one in the middle and the others as far to the sides as they'll go. The gives 18" spacing for the lights (center to center), just a 6" gap between them edge to edge and 12" from the edge of the light and side of the tank. I think that gives the most equal spacing from between LED pucks but leaves the edges fairly shaded, maybe too much to stick acans or favias on the sides of the tank. It also leaves the front and back of the tank more prone to shadowing though hopefully the T5 bulbs will reduce that enough.

The other option is to buy their 24" spacing kit and turn the Radions so they're front to back. Maintaining the 18" between lights (center to center) gives me an 11" gap between the lights and a 14" gap from the side of the tank to the edge of the light. In turn I should get much better front to back coverage, potentially a little less hotspotting between lights but a little less light on the edges of the tank. I'm also worried that the increased spacing between the T5 bulbs will cause too much light to spill out the front and back of the tank and not give enough coverage in the middle. It will also cost more to buy 3 sets of brackets and the new 24" endplates.

I mocked up both options in 3D and I'm hoping you guys can help me come to a decision. Right now I'm leading towards the first, simpler option.

 

[Hemmdog]

Shadowing is going to be pretty rough with that short of a hybrid. I would either get the longer hybrid or factor in cost of two XR15’s on goosenecks or something to mount to the hybrid and angle at the edges. Easiest would be just get the longer hybrid, then return or sell your current one.

 

[amps]

Shadowing is going to be pretty rough with that short of a hybrid. I would either get the longer hybrid or factor in cost of two XR15’s on goosenecks or something to mount to the hybrid and angle at the edges. Easiest would be just get the longer hybrid, then return or sell your current one.

Thanks. I really wanted to go with the longer fixture but the 60" bulbs draw roughly 50% more power over the 48" and the replacement cost is a little higher. The fixture cost was also $250 more than the 48" which meant the difference between buying a new sump and hodgepodging something together.

Thanks for suggesting adding the XR15's on the ends, I hadn't thought of that. It'd be pretty easy to add one on each end and slightly angle them in for better coverage if I find the ends of the tank are just too dark.

 

[PerplexyHexy]

Hey guys! I've got a 180 gallon tank that I'm about to start rebooting. It measures 72" x 24" x 24". The goal is to have it be 75% SPS, 25% LPS.

I've picked up a 48" Aquaticlife hybrid fixture and my plan is to mount 3 XR30 G4 Pro's in it. Now because I didn't opt for the 60" model due to extra cost and electricity usage, I'm stuck figuring out how to space the Radions to get the best coverage without excess hot spots or shadowing. The default mounting option is to stick one in the middle and the others as far to the sides as they'll go. The gives 18" spacing for the lights (center to center), just a 6" gap between them edge to edge and 12" from the edge of the light and side of the tank. I think that gives the most equal spacing from between LED pucks but leaves the edges fairly shaded, maybe too much to stick acans or favias on the sides of the tank. It also leaves the front and back of the tank more prone to shadowing though hopefully the T5 bulbs will reduce that enough.

The other option is to buy their 24" spacing kit and turn the Radions so they're front to back. Maintaining the 18" between lights (center to center) gives me an 11" gap between the lights and a 14" gap from the side of the tank to the edge of the light. In turn I should get much better front to back coverage, potentially a little less hotspotting between lights but a little less light on the edges of the tank. I'm also worried that the increased spacing between the T5 bulbs will cause too much light to spill out the front and back of the tank and not give enough coverage in the middle. It will also cost more to buy 3 sets of brackets and the new 24" endplates.

I mocked up both options in 3D and I'm hoping you guys can help me come to a decision. Right now I'm leading towards the first, simpler option.

Your 24” bracket idea is your best bet if your stuck with the 48” and the xr30s. You will have a gnarly 1’ on each end of the tank that will not have adequate lighting though... I have a 72” tank as well... im using the 61” hybrid with 5 xr15 pros and its perfect for that tank size... just trying to give you input from what I have seen on my tank...

 

[amps]

Your 24” bracket idea is your best bet if your stuck with the 48” and the xr30s. You will have a gnarly 1’ on each end of the tank that will not have adequate lighting though... I have a 72” tank as well... im using the 61” hybrid with 5 xr15 pros and its perfect for that tank size... just trying to give you input from what I have seen on my tank...

Do you find the T5's give enough light in the middle of the tank with that arrangement? I'd almost be tempted to angle the reflectors in if it was possible.

 

[Hemmdog]

The t5’s don’t get the middle of my tank super well. These are new and angled

 

[PerplexyHexy]

Do you find the T5's give enough light in the middle of the tank with that arrangement? I'd almost be tempted to angle the reflectors in if it was possible.

Dude, its more than enough light... it looks great... you will like it much better... it lights the tank just right... I have both my fixtures at 12” above water... And the amount of electricity being used on the 61” compared to the 48” is minute man... you will hardly tell a fifference

Edit: thought you were talking about the 61” fixture... yeah, your gonna have an issue with the middle of the tank using the 24” brackets... but thats where you will have to space your xr30s where the spread overlaps perfectly and you dont lose much... also height will be important... just seems like more of a headache to try and make the 48” work instead of going the 61”...

 

[PerplexyHexy]

Its pretty much pointless to run the 24” brackets, unless you have a wide tank... your best bet would to pay the extra and get the 61” hybrid and save the money on buying the xr15s instead of the xr30s... that would be your ideal setup and you wont be disappointed... It would be a nice clean setup and would light the tank perfect