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The Goldfish Sanctuary

The Quarantine Tank

A quarantine tank serves two purposes in fishkeeping. First, it is a good idea to quarantine new fish in a separate tank for two weeks before moving them to the main tank. This helps to ensure that the fish is healthy before he is brought into contact with your other goldfish.

Another reason for having a quarantine tank is in the event that your fish has become sick. A sick fish is often best separated from the main tank to eliminate the chance that he will infect the others. Once there, the fish is treated until well, then returned to the main tank after a few more days of observation. Although it is true that sometimes you will want to treat the entire main tank, very often it is most beneficial to isolate just one or two fish for treatment.

Benefits of using a Quarantine Tank for Sick Goldfish

Risk of infecting tankmates is reduced
Main tank is not greatly disrupted
Biological filter will not be harmed by medications
Live plants will not be harmed by medications
Less medication needed if quarantine tank is smaller than main tank
Fish will not be harassed by healthy tankmates

Setting up the Quarantine Tank

A quarantine tank is often smaller than a regular tank, and because it is to serve only as a temporary home, this is acceptable. You must first obtain a small tank. A ten gallon tank will be acceptable for one or two fish. You will also need an airpump and airstone, plus airline tubing. Aeration is especially important in a quarantine tank because the size of the tank is often smaller than usual, and medicines sometimes take oxygen out of the water.

Lastly, find something to cover your tank with so that the fish don't jump out. Nothing else is needed. The quarantine tank should be relatively bare. This will make cleaning much easier. Your fish may be reassured by the presence of some plastic plants or hiding places, however. You may wish to include some of these. Lead anchors are sold that can be used to hold a plastic plant in place. Also, since the fish is reassured by a dark bottom, you can place the tank on top of a dark mat or piece of cardboard if you wish. This will show through the bottom of the tank.

If you do decide to use a filter in the tank, make sure there is no activated carbon in it.

Place the quarantine on some steady, flat surface which will be able to hold the weight of a full tank. It is a good idea to put some water from the main tank into the quarantine tank to avoid stressing your fish. If your main tank is very big, this will be no problem. If your main tank is somewhat small, adding just a little of the water will also help. Take water from the top of the main aquarium. This water is always the cleanest.

When your quarantine tank is full, attach the airstone to the airpump with the plastic tubing. Then place it in the tank and weigh it down if necessary so that the stone is at the bottom of the tank. Next, add any decorations like plants or hiding places. Make sure all of these are soap-free and aquarium-safe.

If you decide to install a small filter, do so now. It will help to keep the water clean. If your purpose is to treat sick fish, don't add any filter carbon. If you are using the quarantine tank to observe new arrivals, carbon may be added.

Note - any equipment used for the quarantine tank should not be shared with the main tank. This aviods the possibility of passing infection to the main tank.

Moving the Fish to and from the Quarantine tank

Use a clear, clean plastic bag to catch the afflicted fish. Using a net is not advised (it could injure your fish). If the water in the quarantine tank came entirely from the main aquarium, you may place the fish into the quarantine tank immediately. However, if the water in the quarantine tank is different in any way from the water the fish was previously in, or if this fish came from the petstore, a period of acclimation is needed.

Acclimating your Goldfish

Tie the bag shut but leave plenty of air in it. Float the bag in the new tank for 15 minutes. Then, over the next few minutes, add a little more water to the bag from the new tank. When this process is complete, open the bag and let the fish swim into the tank.

Observing Fish in Quarantine

Remember that moving a fish to a new tank can be in itself a stressful experience, so you will want to keep a close eye on quarantined fish. Treating fish disease is not yet an exact science, and usually one medication is used to treat several similar ailments. Further, it is not always easy for a beginner to accurately diagnose a fish's ailment. Because of these facts, the best way to determine your fish's condition is careful, patient observation. Don't forget to stay in touch with your local vet or petstore, especially if further complications develop.

Keeping the water clean is important for several reasons. Most importantly, because goldfish produce more amonia than many other fish, they can literally poison themselves when kept in a tiny tank. Daily partial water changes of 20-25% are suggested during quarantine. (Filters with activated carbon often take medicine out of the water, and can't be used when treating sick fish). A water change is best done 1 hour after feeding time, for this is when fish are most likely to expel waste.

Some medications can be used together, but some cannot. Read and follow all instructions carefully, and contact your petstore when in doubt. If one medication fails to work, and you wish to attempt another which is not compatible, be prepared to do several days of partial water changes after you finish the first treatment before attempting a new medication. This will help to dilute the original medicine and minimize the chances of a negative reaction. If your fish is in bad shape, however, you may have to add the new medication sooner, in which case you should do about a 90% partial water change before adding the new medication.

When the fish is cured, keep him in the quarantine tank for another 3-5 days to ensure that the condition does not recur. When at last it is time to place the fish in general population, catch the fish in a plastic bag and go through the acclimation procedure (see above). Try to remove as much of the quarantine water as possible (replacing it slowly with water from the main tank) before setting the fish free into the main population.

Closing Down the Quarantine Tank

When your quarantine tank is once again empty of fish, it is time to close it down. Because medicines and diseases may have been present in the quarantine tank during the time it was up, it is important to clean it and all equipment very well before storage. If you are not absolutely sure that your tank is free of disease, you may want to continue medicating the bare tank for a few days to make sure it is sterilized. (Another way to kill freshwater diseases is to add a high concentration of salt to the water... freshwater bacteria or fungus usually die in a very saline solution. Just make sure there aren't any fish in the tank when you attempt this precaution!) Any other equipment that may have contaminated can also be placed in the tank. Continue to aerate the tank during this process... discard airline tubing when the process is complete.

Drain the tank completely. Rinse all the equipment well in hot water several times. Salt makes a good cleaning agent in place of soap or detergent. When all of the items have been well cleaned and rinsed, it may be allowed to air dry. Setting the tank and equipment in direct sunlight for 4-5 days is the most effective tecnique. If you do decide to wipe it clean, paper towels are suggested over cloth towels. The latter may contain soap deposits.