I'd only pull them all if you want to lower your fixture.
A quick rule of thumb:
With 90º lenses, your
mounting height equals the radius of coverage that the emitters will provide.
So 90º lenses at 12" off the water gives you a 12" radius of coverage. (Remember: radius is 1/2 the diameter)
With 60º lenses at 12", you radius shrinks to about 7"
With 120º lenses at 12", your radius blows up to 21"
But experimentation with combos of lenses like Salty is also fun!
It also takes the 60 and 90 beams and let them do a full 140 or so
Just a build question.....aren't the emitters on those "sumberged" in the housing by 1/4-1/2" like the ones in my gu10 bulbs? So when you take out the lens it leave the emitter in a little hole?
Maybe not cuz I've seen other black box designs,
but if so then using no lens is slightly more limiting than using 120º lenses because some of the light is clipped at the fixture opening with some probably even being reflected back into the fixture.
Adding the 120º lens in this case brings more light out of the fixture. It's just a percentage –
and it's still gonna be A LOT wider than 60º lenses! – but if you're planning then it could matter.
Reading all the mania about disco balls and wide angle lenses back when I was puttng my gu10 fixture together had me worried about the
30º lenses those bulbs use by default even though it was accounted for in the design and setup....so I orderd 3 bags of 50 replacement lenses to play with: 60º, 25ºx50º and 120º. Turns out 30º is fine....properly designed for the application accounting for the mounting height, tank surface area and shape, then the actual lens angles don't matter a whole lot. I have a lot of extra lenses now.
