I mix kalk and r/o to a think paste and add lemon juice to the mix. Get it thick enough it will barely go into syringe. No needle as it actually seperates the mixture and just releases the water, leaving the kalk packed in the syringe. With it that thick you can just squirt it all over the place the aptasia is and it will completly fill the rough jagged places and then dries almost like cement sealing them in a kalk tomb. I had just one little rock with a couple on it from LFS and in no time they spread to other places. Best of luck