I replied to the first thread. I think if the fish can specify a subtle difference in color at 20ft on a dark moon
( and I bleive they can)
then they can definately look up at a black sky and see a bright glowing purple light that signifies things are out of the ordinary and bigger fish shut down.

Dim the light down with painter tape and point it up on the gunnel not toward the water. That might still bother fish if theyre really innactive but you gotta see your line.

I use cheap black lights and I probably night fish more than anyone on this board or in this state for that matter.

If you have poor vision Im not the person for advice on blacklights.