Introducing Fish into the Tropical Aquarium

Many people receive fishes shipped from out-of-town sources. Often prompt and proper action must be taken upon their arrival to insure their continued life.

Examine the carton carefully before opening it. If it is wet or damaged, mark the fact on the receipt before signing it. Make the carrier wait and watch while you open the shipment. Check the water temperature immediately. Do not remove any fishes which appear to be dead, unless they are obviously decayed or physically damaged. Many tropical fish can be revived.

If the water is below 70° F., it is important to warm it to a higher temperature. Do not remove the fishes and put them into other warmer water. Instead, add warm water to the original water. Stir as you add the warm water to prevent hot water from touching the fishes. Warming the water slowly is dangerous. The fishes may die before the water gets warm enough to help them.

Once a desired temperature has been reached, change part of the water for fresh water. If the original water was foul, continue making partial changes at intervals until the water is clear. The water which is dipped out is thrown away. This process over a period of hours will give the fishes a chance to adjust to the different composition of your water.

Fishes bought from local source are usually brought home in a small container. These containers should be allowed to float unopened in the aquarium for fifteen minutes. This allows the water in the container to equal the temperature of the tank water. Remove the cover carefully. The fishes are likely to jump as soon as they see the light. Partially submerge the container slowly so that some water from the tank gradually runs into it. Pour out part of the water and repeat. Do this several times before completely submerging the container and letting the fishes swim out.

When transferring fishes from one tank to another, the same procedure is followed. Dip some of the fishes’ own water out in a container and place the fishes in that for transferring. It is unnecessary to float the container first,

Many aquarists maintain newly acquired fishes in separate tanks for ten days or two weeks. This helps to reveal any latent disease before it might be transmitted to the other fishes. During this time strict isolation is practiced. Utensils (net, dip tube, etc.) are disinfected, water drips are avoided, and even hands are scrubbed and rinsed thoroughly before going from one tank to the other.

A fairly good isolation ward for two or three small fishes is a squat one-gallon jar floating in the aquarium. By experimenting with the amount of water in the jar you can determine the proper amount to keep it upright and buoyant. This type of jar can be used for breeding also. A breeding trap, with its perforations which permit the circulation of water, is of course valueless for isolation.