Light for red...
Usually those TFC (pinkish looking tube) which we use are more on viewing. but no harm done if they're been left 24/7. Infact, it'll help in maintaining the colouration of the developing red but not that hush on them comparing to using those of the higher intensity tubes.
Tanning is just like we human been exposed to sun for a period of tme and we become darker in tone but we doesn't hold the tan once we stop the tanning process. This apply to the red as well.
When to do tanning for reds ppl may ask. IMHO, it's when the fish is about to go for exhibition or competetion then it's worth doing so.
Red's colouration development depend on it's own maturaity and genes. When the red is mature enough or when it reaches it's colour development age, the colouration even without taning will develop nicely.