Think your right russel , but have a look at my copperband xxl....If you want to kill the overflow jerks I did it. I have never been so proud after fighting a war with aiptasia I think I rather get divorced. It is hell. But I had enough. So I had at least 25 big ones in the overflow. I shut off the valves so no water was allowed in the sump or coming from tank. I siphoned all the water out of overflow. I took boiling water several pans worth and filled that pig up and added vinegar as I went I let that sit for a day and a half. I than siphoned it all out. All dead jerks. Took a couple of hours. Wiped it down with vinegar let it dry and started the overflow. The war was over. I had won and now everything gets quarantined. Never again.