A long time ago I planned on writing up some actual numbers about this but I figured it was pretty self evident.
We thawed 10 grams of PE mysis in a liter of DI water. FWIW 10g is an amount about the size of a cherry. We strained the water through a 100 micron filter and then tested for PO4. I had to dilute it down 4 times in order to get it low enough to test. It raised the level of PO4 in the liter of water to something like 3ppm. That's only a liter of course but adding that to a 25g tank would work out to a 0.03ppm shot of PO4. That's a hell of a lot if you're doing it every day!
The juice / matrix the shrimp come in is great for feeding nuisance critters. I thaw it in a net with some lukewarm water then shake off any excess liquid.