and more...... http://WHY should a creature 2 days in a bag alive suddenly die when the bag is opened?: poop. Respiration. In shipped livestock, or during a trip home from the store, the waste from the fish/invert hits the water and you have ammonium and co2 in that water. The moment you open the bag, you release the co2 and ph climbs. This ph change converts the harmless ammonium in the water to deadly ammonia. The longer the fish is exposed to ammonia (remember it's drinking it as well as breathing it) the more damage its internal organs take. Too long in the opened bag and the fish takes too much damage to live very long. -------- First, you should know (phone) at what salinity your shipper ships certain livestock. They'll tell you. You should have a qt tank ready AT THAT SALINITY if you've got a fish. You can put inverts straight in. ---------- Step 1: DO NOT OPEN THE BAG. Float it for 15 minutes. This handles temperature. Step 2: open bag and test the water to be sure you were told accurately. AS OF THIS EXACT POINT (look at the clock) YOU HAVE 30 minutes OR LESS to get that critter to a qt tank, if fish, or to your tank, if invert, and to dip it and set it safely on the bottom of your tank if coral. Remember acclimation is all about salinity. Be accurate. Be fast. If salinity matches within .001, that fish is good to go into that qt water. Instantly as you open the bag if you've got a near match!