Welcome! Glad you found us.
Don't put Caulerpa in your display - I don't mean to sound harsh, but I promise you you'll regret it. Especially once you get your new lights.
The stuff will grow like crabgrass, is extremely invasive, and is
evil to remove.
If you don't have a 'fuge or sump, when you swing by, I'll definitely give you some Chaetomorpha (Brillo pad algae). At least, for a macro, it won't attach itself to your rock (and around, and under, and within, and .... )
You also need to be very careful with Caulerpa's going 'sexual' - which they are very likely to do if not lit 24/7. When this happens, they will release all the nutrients (nitrates, phosphates, etc.) that they have absorbed over time back into the tank's water. Not a good thing.
HTH!