Hi All, I’m in a bit of a conundrum with my Caulerpa…. I bought some caulerpa a few weeks ago which I put into my Refugium. After a few days I noticed the grapes on the tops of the caulerpa was going translucent, almost like the green was being sucked out of it. A couple of weeks later the volume of the plant had decreased to less than half its original size. Until this point I had a peppermint shrimp and 2 dwarf red legged hermits in my Refugium, I thought the crabs may have been having a go at the caulerpa so I put the two crabs back in the main tank leaving my peppermint shrimp in there on his own, thinking this would solve the problem. The following week I had to go away with work for a few days, when I got back the caulerpa was dead! Don’t think moving my crabs made any difference so now I have two theories My lighting. My Refugium is lit using a 7watt 6400k bulb which is set to run reverse daylight hours. In the top of my fuge I have cut a piece of Acrylic which is used to stop water from bubbling up and causing too much evaporation right next to my sockets. Is the bulb strong enough and the correct temp? Could the Acrylic sheet be filtering out all the “good light”?? Flow Rate. There’s not a lot I can do about the flow though the fuge cause this is determined by my overflow and return pipe work and pump. I have a Eheim 1250 universal which I have on a isolation valve which is usually open about 75% which means I’m getting roughly 330Gallon per hour through my fuge is this enough? I don’t have any algae in my sump at all now but would like to get something I can maintain in there as soon as possible!