Many organisms are lost due to inadequate, improper acclimatizing. Collectors, distributors, transhippers, wholesalers, retailers and hobbyists suffer most of their losses in the process of receiving new livestock. When placing fishes, invertebrates, algae, and live-rock into a new environment there arises the possibility of physical, chemical, biological, even social shock. This Section shows how to avoid these stresses altogether, or ameliorate the effects of stress after it has occurred. There are a myriad of acclimation techniques; depending on the stock's genetic and developmental history and conditions at shipping; all are to some degree appropriate and successful. However, many losses can be avoided or reduced with the information provided here. An Overview of Livestock Stressors:

Physical: To many fishes, even a small change in temperature over a short time is detrimental; thus attempts are made to equilibrate the temperatures in the new and old environs. Often this is done by floating the plastic shipping bags the fishes are transported in the aquarium. This process should continue for 10-20 or more minutes, depending on the amount of water shipped, the temperature difference, and the apparent strain the stock is undergoing. It's often a good idea to monitor the temperature in both environments. Opening the floating bag is not a good idea as the concentration gradient of oxygen may be higher if left sealed and an open bag ...

Continue to read all article at : http://www.wetwebmedia.com/acclimat.htm