I just pour out about 1/2 or so of the bagged watter, and slowly drip in water right from the tank until it gets to about double, then dump about half of that water out and drip in more water from the tank, until it again reaches double the amount. I float the bag in the tank while I do this. Once the bagged shrimp has been done two times like this, I dump out just about all of the water in the bag and for the final time allow it to drip in the bag one more time, and then just allow the shrimp out of the bag........Total acclimatin may take about 1 hour tops, and I have yet to loose any shrimp. The local fish store, simply takes the big bag of shrimp they get in and float the bags, sample SG and if its even close just do a temp acclimation.....no drip or water added......I had always been paranoid as I have always heard they were pretty fussy as to how they were acclimized, but from the shrimp I have done they don't seem hard at all and its relatively fast and easy.