A quarantine tank should be part of every serious aquarium keeper. It does not have to be large, as long as it is adequate for the size and number of the fish to be observed in it. The interior arrangement and water quality should match, the future home of the fish in the permanent aquarium. Make sure, however, that all of the decorative items can be removed when fish must be treated or caught.

All new additions should be kept in quarantine for three to six weeks and their well-being checked daily. Three weeks is the minimum time to quarantine fish that were raised in aquarium, development of many parasites can take up to two weeks before reaching a stage at which the signs of a disease becomes apparent. Five to six weeks are appropriate for fish captured in the wild or fish raised in ponds, which often harbor unrecognized parasites. During this time, transfer some water from the aquarium into the quarantine tank to start adapting the new fish for their future home. The second function of the quarantine tank is that of a hospital tank for fish suspected of being diseased.

Diseases that are recognized late are difficult to treat. If the whole fish population should perish due to an epidemic, it is advisable to thoroughly disinfect both the aquarium and the quarantine tank. Destroy the plants; with pathogens higher on the evolutionary scale than bacteria and viruses, disinfection of plants can be considered. Decorative items, roots, rocks, gravel, and filter contents should be boiled for one hour, without counting the warm-up time. Sterilize the empty aquarium and the non-boilable objects with a strong potassium permanganate solution. Let the filtesr run without substrate so the container, pump, and tubing are disinfected at the same time. Set up the aquarium again after all the parts, including the tank, are thoroughly rinsed. After starting up, the filter again needs a running in time of six weeks until adequate numbers of bacteria have built up.

Examination of Fish:

When a fish falls sick and poisoning of the water can be eliminated as a possible cause, immediately transfer the fish to the quarantine tank. Examination begins with observation (See Charts 1 through 4); a definite time every day must be devoted to it. Any irregularities observed must be recorded so that later on the whole course of the disease can be documented. The documentation can be kept for future reference, it should also contain the "patient's" history, behavior, date of last water change, chemical quality of the water, last feeding, etc. The following key words can be modified according to individual needs. (YOU SHOULD NOT, UNDER ANY CIRCUMSTANCES, EXAMINE VENOMOUS FISH!)

Behavioral changes usually appear in an advanced stage of disease, so that immediate treatment of the fish is called for. For that, trap the fish in a net against the wall of the aquarium and examine its skin closely with a magnifying glass (See Charts 5 and 6). The larger parasites, like the carp louse and Ichthyophthirius, are easily recognized. Further examination requires that the fish be lifted briefly out of the water. The ocular reflex can now be tested. As shown in Photograph No. 36, the fish attempts, when rotated around the long axis, to keep looking horizontally, so rolls its eyes to counteract being held on its side. If its eyes remain in a normal relationship to its body, then it is affected with a labyrinth problem.