so i talked to the local store (which they have this) and there are two versions. The fresh and the concentrated. The concentrated is just that BUT it can last a LONG time in the fridge.
Lasty the owner said he talks to the manufacture which (behind the scenes) they say DONT follow the directions. Way too much. Which is good news, because it will last longer.
So to answer your question i do about a table spoon (in a small turkey baster) and squirt some in the bottom of my refugium, which is low flow. That's it.
I do it a couple times a week up to four times.
When the tank was fishless the bugs made it to the display, and i kid you not.... the glass looked like someone salted the glass. Tons of bugs including mysis shrimp (no idea how they got in).