We have the same thing in our display. I think someone IDd it as red sea grapes, but not sure how accurate that is. Ours grew steadily for a few months then seemed to max out. After a trim, it grew again and seemed to stop again. Check with your LFS, one of ours wants as much as I can give him and he'll give me discounts for it. I'm just afraid to cut too much cause we like it too and dont want to lose it. I found that it doesnt behave like grape caulerpa, more like a real plant. Never seen it go sexual or spread like g. caulerpa, it seems only to branch out like a tree. If you like it, dont worry about it and just trim it. The only problem I see for you is light competition with the zoos. Your zoos may start growing long stalks reaching for light. I was beginning to think we were the only ones with this stuff. Going to get a pic to show ours, will post it in a few.
