How to Properly Quarantine Your Fish

Quarantine. It is one word that all fish owners hate to hear. Quarantine defined is isolation in order to prevent the spread of disease. In the fish world, this applies to any new fish being added to an existing population of fish, or a sick one who needs treatment. When you have a tank of fish and you want to add more fish, you must quarantine the new additions in a separate tank with separate equipment before adding them to your tank. Now is the point where people groan and sigh, and say that they quarantine, but never really do. Now read the next part very carefully:

Quarantining your fish will save you time, money and lives.

Maybe the lives of ALL your fish.

Even if you know where your fish came from, it is important that you ALWAYS quarantine new additions for 4-6 WEEKS MINUMUM. More groans and sighs, I know, but treating one or a few sick fish is a lot easier and less expensive than treating a whole tank load.

When a fish is transferred from its home environment to an alien one, it causes a stress response. Similar to the stress response in humans, excess cortisol results in a decrease in the fish’s immune capability. This lowering of the immune defenses allow for any subclinical infections (there, but not apparent) to become clinically apparent. That one little Ich or trematode suddenly has the green light to reproduce and flourish. In just a few days, the lowered immune system has resulted in a very sick fish. But, since you smartly kept him in your quarantine tank, it is just the one fish that gets sick. If you had hastily put him in you tank with all your existing fish, you would now have a tankful of sick fish. It is much less expensive and time consuming to treat one or two fish in a quarantine tank than a whole tankful of previously healthy fish. And if the worst should happen, you only lose one or two fish, not all of them.

A true quarantine system is completely isolated from the main tank. This means separate water, décor, and equipment. Yes, even equipment. Some bad critters, known as pathogens, can hitch a ride on equipment transferred between tanks. If you absolutely must use the same equipment, soak it in a 10% bleach solution for at least 15 minutes and rinse thoroughly before using again.

Quarantine tanks are also very handy for sick fish. An extra tank can be used as a hospital tank if a fish were to get sick. Getting a sick fish off on its own can decrease extra stress and make it easier to see how they are doing.

Some fish distributors may offer to quarantine your fish for you at their facility. This may be a very practical solution for those fish keepers who do not have the space for a quarantine tank. However, make sure you ask what their protocols are for quarantine. If you think about it, moving a fish from one tub to another 15’ away with similar water is not too stressful for a fish. This may not be enough to decrease their immune system significantly. However, if a fish was just shipped overseas, this fish underwent a very stressful event, significant enough to have the fish go through a proper quarantine. Make sure you know where and how your fish is getting to you in order to determine if a given quarantine protocol will be enough to lower your fish’s immune system significantly. Remember, without this lowering of their defenses, your fish may bring home some nasty bug that can wipe out your entire tank or pond population.

So, in conclusion, quarantine is your friend. When done correctly, quarantining new or sick fish can save you a lot of extra funds and effort, not to mention save the lives of your aquatic pets.