The Christmas tree plant (Rhipocephalus phoenix), is a calcified macroalgae that resembles members of the penicillus genus. It is also known as "Pine cone Algae". Growing to a size of about 4 inches, it will not be eaten by fish or snails, making it ideal as a display piece.
This algae is capable of living under low-moderate light, it will grow strongest in moderate to high lighting. We send Christmas tree macros approximately 3 inches tall. All macros present some risk of going sexual and releasing carbon dioxide into you aqaurium. However, the risk of adverse ph changes from the release of carbon from this species is extremely low. It should be planted into your substrate, a substrate greater than 3 inches deep would be ideal.
Spring and Summer are the best seasons to get this algae. However,we have to get it from MLE licensed divers, and sometimes have a problem controlling quality. Right now the specimens are running a little small, hence the smaller price. They grow...:)