Oops I didn't see it was multiple choice.
I added my vote for chiller then.
I have a wavebox as well, and while I agree that it is a great piece of equipment to have and I've never seen my corals with such incredible polyp extension. I don't think I would have any problems going without it as my Tunze powerheads were getting the job done for me before I got the wavebox. Not that I'm saying the wavebox isn't great, its just not a neccessary piece of equipment IMO. Just as a ca reactor or chiller isn't necessary if you don't have a tank crammed with sps or your tank is in a cool basement or something
As for the aquarium controllers, they're out of my league. I have read up o them several times and I still don't really "get it"
