Originally Posted by oyf709
It depends on the fixture to be honest, I have talked to many LED
manufacturers and all of them provides me 60 degree lenses as default and 120 degree was not an options, even if I ask them. I also don't see why you want to spread the light to 120 degree at the same time for your tank. A LED
fixture suppose to work best at 90 degree with about 6 to 8 inches above your tank.
Here's what I'm talking about. In this first pic of a led
, the clear plastic bubble on there is a 120deg. lens
If you add another lens like this second pic, that's different, but by default they generally come with 120deg.
This pic is not what I'm talking about, below