I used a 5L sprayer. Dilution was roughly 1:4. Sprayed it on, left it (should have worn a mask, did wear safety specs and old clothes that could bleach easily). Watched it work before my eyes for about 15-30 minutes. Topped up a few places where it had soaked in and hadn’t had as much effect. Washed it off with the hose. Although it washed into the adjacent hedge it didn’t affect the plants, it may do with some more delicate plants. Path dried and looked cleaner than whenever I had pressure washed it previously. It continued to bleach a little more over the next few days and a year later none of the lichen or moss has grown back - it’s a shady side of the house and just a few months after pressure washing it would all grow back.
My biggest problem with our path and jet washing is that it can too easily wash out the stuff in the joins between the slabs.
Biggest tip would be to do it on a day when your windows are closed because it stinks, but the smell soon fades.
