This is going to be a really dumb question, but this is the first time I’m mounting lights directly from the ceiling so I don’t want to mess it up. How do you really determine the placement of the lights? In this past I have only had to put a single light over my aquariums! I figure this probably isn’t too hard to figure out once I have them but some expectations before I go in would be really helpful.
I believe your aquarium is 6’, same as mine. Would you be willing to tell me how far from the edges are your lights and how much space is in between them in the middle? Just so I have an idea of where to place them?
Panel width is 24". Tank is 72".
Symmetrically it would be 8..24"..8"..24"..8"
Light is 24" x 18.5"
But as mentioned above that will generally form a hot spot in the center.
Best to widen the gap in the middle.
This gets tricky because height, front to back distance and the panels effective beam angle all come into play.
At a effective angle of 100 degrees and hanging height of approx 7" light face to water line the symetrical spacing has little spill on the sides, more on the front/ back " if" the tank is less than 30" wide.
7"...24"...10"...24"..7"...
Should somewhat even out the par difference along the entire 6ft with a bit of spill on the sides..
Note the higher the hanging height the more spill. The more narrow the led lensing the less spill.
You can determine best height using a phone lux meter app and a sketch of your tanks surface area by 1/2 in your case with 2 lights.
So a 36x24 outline.
Setting up a 6x2 area and hanging 2 lights is ideal though a bit cumbersome
It would allow you to judge the effects of the gap size as well as front/ back left/ right effects.
You just want relative numbers like at 7" the lux changes from x to 1/10x 12" from the center. Gives an idea of possible spill
Retaining photons in the tank as much as possible is the goal
All based on math and a few assumptions not on real life.
The 100 degrees is a compromise between the usual 90 to 120 degree angles generally used. Diffusers complicate things. I believe the pro version did away w/ the diffuser(?).
The height is below ati recommendations but that is a generic assumption.
I don't believe you gave your full tank dimensions.