I use the same method about every 2-3 weeks. I also use Fish Emulsion. I usually fill it up about an 1/8 of the way with the Fish Emulsion and add the rest with compost tea. I beleive the MG sprayer will spray out 50 gallons ( I think I read this on the website or on the bottle). But 50 tbls seemed a little high to me. My plants have been growing fine with the amount I am using. Maybe someone else has a more presice method.

I would never put any chemicals into any portion of a home water supply line, including a sprinkler. I don't even like the hose-end feeders where people use weed killer and so on.
What if a tiny bit backflows into your house water supply and your kid drinks it and gets sick ? It isn't worth the chance.

I understand your concern kachinee, and I'm sure in some circumstances there is a chance of back flow contamination. However, I have 50 feet of hose between the garden and the faucet. And, when I tested this setup over the weekend, the fertilizer tank was emptied in about 20 minutes. After that I disconnected the feeder and continued to irrigate with plain water. I see no chance of back flow contamination as long as I follow the same procedure. I'm glad you brought up the point though. To be honest, I hadn't thought of that possibility.

My drip system has a backflow preventer. I sure hope it works. I never thought of it like that.