Ah, you wanna do softies, sorry the first method I posted was for hard corals. For leathers and shrooms, get some rubble and put it in a small plastic cup or bin that you use for food storage. Then put the frags in the bin. The bin will keep them from being buffetted too much by the current so that they remain in-place while they re-attach their foot. Usually in 7-10 days the frag will have attached itself to one or a couple pieces of rubble at which point it can be removed and epoxied in place
.
Dunno about specific brands TBH, especially not what's available in the UK. I just bought mine from my LFS