Ever since plastic bags have been used to transport aquarium fish, hobbyists from around the world have utilized a simple method to acclimate new arrivals. This process, commonly called "floating and dipping", can be quite effective in reducing stress in transported livestock if employed properly, but equally effective in causing stress if misused.

Why Acclimate?
As a general rule, fish in nature are not required to adapt to sudden changes in environment. A given area in a large body of water usually does not fluctuate chemically or in temperature in rapid order, and even when an abrupt shift does occur, fish can often relocate to an area more to their liking. As such, when fish are exposed to unavoidable severe change, whether in nature or an aquarium, the result is stress, which in turn may lead to illness and even death.

Acclimation serves to reduce such stress by allowing fish more time to adapt to changes in their environment.

When NOT to Float and Dip
Since the whole point of acclimation is to reduce stress, it should not be forgotten that the very acts of floating and dipping can be stressful. Fish often panic in such situations, able to see safe harbor in their soon-to-be home, but unable to get there. Also, in some cases, fish have been in the confines of a small bag full of fouled water too long already, and floating only extends their misery.

There are two extremes of conditio ...