The Best Way to Acclimatize New Marine Fish to Your Saltwater Aquarium
What we must consider is why we need to acclimate in the first place.
The Ocean is a volume of water so huge that the salinity, pH and temperature generally fluctuate very little and very slowly. As such, many marine creatures are unable to cope with the shock of rapid changes in these parameters. What we are trying to achieve during acclimation is, in a controlled manner, to slowly and gradually adjust the salinity, pH and temperature of the water that the specimen arrives in, to that of the water in the aquarium.
The method of floating a bag in your aquarium adjusts only one of these parameters - the temperature. It is worth bearing in mind that a small bag of water adjusts to the temperature of a much bigger surrounding volume of water relatively quickly . If your new purchase is in relatively cold water when you get the bag home, it could be quickly elevated to the warm temperature of your aquarium in as little as 15 minutes after you float the bag. This could be a change in temperature of 5 degrees Celsius (41 degrees Fahrenheit) or more, and is something that would not be experienced in the creature's natural habitat.
Therefore, a method must be used that not only adjusts the temperature in a more controlled fashion, but also accommodates for the difference in pH and salinity of the two volumes of water. Our recommendation is to use the drip method of acclimation, whereby your existing aquarium system water is very slowly dripped into a container holding the fish or invertebrates in the water they arrived in. This process takes a minimum of 3 hours, with gradual increases in the amount of system water being introduced to the new arrivals. Many aquarium hobbyists agree that this is the best way to ensure that your new animals are acclimated to your system with the least amount of stress. It is important to understand that the volume of water your new specimen arrives in is very small compared to your aquarium. The initial stages are therefore very important and the initial water drips must be very slow.
Some species of fish are indeed more sensitive to the changes experienced during acclimation, but if you remember to take things slowly and monitor the fish or invertebrate constantly during the drip acclimation process, you will find that you experience great results.