question about zooxanthellae

have a question about zooxanthellae, is it what gives coral its fluorescent type coloring. i brought an open brain coral home about 2 months ago, have noticed that it has gotten much greener, esp when daylights go off and just actinic are on. the LFS i bought it from isn't to impressive, and have decided anything that that is doing "OK" in their tank will flourish in mine.

reason i am asking is i bought a frogspawn today, looks pretty good but lacks some of the real bright green i have seen in others. it has 5 heads and i got it for 50 bucks, which i think is a pretty good price. i am hoping that it will respond the way my trach did. getting brighter.

is the difference in color of the same species different types of zooxanthellae, i thought i read that somewhere

ill get some pics up tomorrow maybe once it opens all the way

 

You are correct in your assumptions. Many corals will either color up or dim based on the spectrum and quality of lighting they are put under. Sounds like you have some happy coral conditions in your tank.