This is a difficult tank to light due to its depth. I have a 40 gallon high, same depth, and it has proven quite difficult.
My recommendation would be to have at least 1 ray 2. This light puts off the most par and would give you the most bang for your buck. It also depends on what type of plants you want to grow and wether you will be injecting co2. If you want high light you may need two ray 2s or a ray 2 and a planted+. More info would help us tell you what would work best!
I have a 37G (30 1/4 x 12 1/2 x 22 3/4) that I have a RAY II on and am adding a planted+ to tonight.
I can see what people were saying about "spread" .. I'd definately see the difference. On a 46 bow or 40 breeder I'd have to say 2 lights are definately needed! I'm putting mine on a 55 so it's not that deep front to back. I'll definately get another one when I have the cash.
Do you have co2 and how will you have the lights mounted?
Yes I do run CO2, it is controlled by my Apex to come on just before my lights come on and shut off once the PH drops low and when the lights go off for the night.
The lights will be mounted to rest on the rim of the tank under the canopy. I just purchased one of the Planted+ to give it a shot.
Currently I have a marineland reef capable light on there just as a temporary light since I got new lights for my reef tank. Love the marineland since it has a built in timer for the moonlights and the daytime lights.
On the Planted+ is the red on with the daytime lights or are they separate too like the moonlights? Depending on how they are set up I may just keep the marineland for the moonlights only and use the Planted+ for my primary daytime lights and control them with my Apex that way. I know I really don't need moonlights as they server no purpose on a planted tank. My kids have some glo fish in there that really pop under the blue light so was keeping it for them since they like it.