red/purple leaves mean "OPTIMUM" level of light achieved

.You have reached the max limit.
My BC and LC's never put out a new growth until the leaves started to turn purplish.
Anthocyanin is a pigment that causes the color change. Anthocyanins have been shown to act as a "sunscreen", protecting cells from high-light damage by absorbing blue-green and UV light, thereby protecting the tissues from photo-inhibition, or high-light stress.
I have a purple flowered phal that the whole underside and top leaves are purple. Thats a combination of light and flower color. Very disturbing from a phal ,until it poked out 2 spikes
You are doing fine!!
Anthocyanin is available for human consumption in many fruits and vegetables everyday. I somehow conceive the idea if we consume to much of this, we turn into Purple Hybrid Smurfs
