We were so full of hope, but a tiny bit sceptical that these would work especially as our local vet said that they were worth a try. However, after 4 months of Charlie only drinking water with the Rocks in the bowl, there has been absolutely no reduction in the grass kill patches in the lawn. We have tried to train her to go in a patch of waste ground beside the lawn, but sometimes she forgets and we're not there on hand with a watering can. Hey-ho.
I love these dog rocks! I've been purchasing the for over 10 years now and they are the only sure way to stop your dogs pee from burning the grass. The dogs don't even notice that they are in their water bowls.