I have no room for a refugium for my 90 gal. I am wondering what the disadvantages of growing caulerpa in the main tank would be. Besides trimming and esthetics, will it hurt corals and other things in the tank?
i dont think it can hurt corals, but that macro can become a pest, in the right circumstances, it can "go sexual" and breed really fast and take over your tank, in that case it can hurt your whole ecosystem, i use cheato, but its not as appealing visually, so i doubt you would want to put it in your tank, but there may be many others that would work, maybe someone else can help with that, but i would reccomend the caulerpa.
Caulerpa is EVIL...do not put it in your main display!! I have no idea how it even got in my main tank but it's there and overgrowing everything eventhough I pull it off daily. If you really need to put something in your main tank put some chaeto balled up in the corner instead.
Level it kinda of can harm your corals when it start taking over everything and smothering them.
if you really want, you can easily get a HOB fuge, or if you have any kind of chamber in your sump, jam some in it, throw a light down there, you can put it in the intake chamber, or anyothers that dont contain pumps, it shouldnt be a problem.
i let my LR sit out on the front deck for 7 months just to get rid of some razor Caleurpa. do not put it anywhere near your system. it will find its way into the display. Gracilaria is a good choice. halimeda is another good choice it still can Holocarpy on you, but it is not near as often as Caleurpa.