Will not wash it away. It washes it in, but not away.

great to know--I was a little nervous that I would quickly rinse away all my work the next day! Also, I used the plans for a brewer on your site and just want to thank you for providing those. I am going to use one mod though: midway through when I removed the teabag and had to switch up the hoses from the small stones to just the big, it was very hard to pull the hose off of the stones and I ended up ripping off the top chunk of one of my 5inch stones. So I am going to just have to sets of large stones and hosing and when it comes time to remove the teabag I will take out the small and big stones and switch them with my other set of stones/hose so that I don't have to do any pulling! Thanks again!

Whether your compost tea will wash in or away will depend on the amount of water that was applied after the CT was applied. Probably an inch of water would help that get down into the root zone, but much more could wash it in deeper or even away.