Kessil AP9x owners: One or two AP9x?

[rpkneumann]

Centre Pompideux is 48x24x28 (actual water depth is about 24" because of sand bed) . Mixed reef.
Had two AP700 but one died (Fan) the other one is near EOL.
Looking to replace them with one Kessil AP9x.

Few questions:
1. Is one AP9x going to be enough?
Kessil spec says yes, BRSTv says no
2. Owners of AP9x. Could you measure the two mounting screw distance for me (center to center)? Also how far are the pair apart. UPDATE: I meant the distances between the 4 screws on the top of one unit.
Thinking of re-using my 4 mounting arms from the AP700s.
3. Are there any softening/diffusing lenses available?
4. Any experience with light pollution at a 10" mounting hight?
Thanks for sharing.

 

[skey44]

1. I’d get two.
2.
3. I’m not sure. I don’t find the light harsh unless you stare into it.
4. I think mine are around 10” I adjusted the height to reduce light spill.

 

[19Mateo83]

I have one over my 36” x18”x 18” tank and am looking for another one to help light my ends more. I run the same 10” height as @skey44 for the same reason, eliminating light spill over.

 

[Tamberav]

No, I have one over my 40 breeder which is 36 and it’s not enough spread imo.

 

[Domoe]

My 140 has similar dimensions. Honestly 1 work do ok but I'm a more is better person.