hi paul, yes they are , got myself some flatworm exit so this is my plan . strip the tank down and put the rock i want in my main tank, in a large blue tub and treat with exit , no lights and water movement, and change water using main tank water. then clean out main tank till totally clean,replace live rock with a large amount of new, and also the good rock i saved ,the rest can go in to my two sumps i have which is a glass 6ft one under my main tank, and also i hav a large blue tub with skimmer and reactors, can you advise on a deep sand bed was going to put one in the blue tub, or the glass sump or my main tank or not at all. then its the waiting game, of testing and adding coral,my fish will be in the blue tub till the corals are added and then i can turn the blue sump on to main tank and add the fish. please advise on this , sorry for the long winded story, but more you know the more you can advise me, thanks paul