Not having any products on hand I tried two techniques with what I did have. First I put the rock with the worst problem into my QT and injected them with pure white vinegar. Killed them instantly then used the syringe to suck out the remains. After 2 weeks about a third of them were back and/or ones I had missed showed up. Next I used kalk paste on them and also on about 10 in my display tank. The next day I reapplyed on one small one that I hadn't hit well. It's been a week so far and none have come back so fingers crossed. As Albert said, I also believe the key is to smother them and fill the hole they come out of.