When I switched from CC to LS I used a wet/dry vac. I removed the fish and inverts, put the hose down to the CC, and turned on the vac. It sucked some of the water and all the debris and CC right up. I then replaced the little bit of water with some I had premixed, and Then added the bag of LS. It took a little while for it to settle down before I added my fish and stuff back, but It worked fine and I had no loss of life. I used a softball sized handfull of my CC tied up in some cheesecloth to help reseed my LS with some of the life I had in my tank. Overall it was not to messy this way and I am 100% happy with the sand.