I have a patio made out of regular patio block in my back yard (small back yard and all is patio block). I have dogs and am concerned about odors and fleas and ticks. In warm weather I use 1 gallon of bleach mixed with 1 gallon water in a 2 gallon watering can. I then sprinkle that all over the patio and let it set a few minutes (don't let it dry completely). Then rinse down with the hose. Takes away odors and kills pests. Also kills any weeds coming up through the cracks between blocks.