Welcome to the forum. Well I agree, any light that would penetrate to 48" is probably too much for reds, as they don't require heating. So I would just go with low light plants at the bottom layers of your tank. I would build a back ground/hill to hike the plants up some. Or just nice tall plants like corn plant, fiddle leaf fig, snake plant, hybiscus, and tea plants.
Phothos is a low light plant that will fill in well and climb.

Red eyes do require some UVB, but only 5.0.