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Used Aquariums

Getting a Used Fish Tank Ready for Use

(The First Tank Guide)

The Used Aquarium

A lot of people get used aquariums, and often they realize (frequently after making the purchase) that they don't know what they need to do with this used aquarium to get it ready for use again. Unfortunately, these used aquarium usually don't have instructions available any more, so much of the equipment may be a mystery and may require some research and puzzling out.

Fortunately, the answer is mostly simple. You just have to figure out which category your used aquarium fits into:

In any of these cases, the used fish tank may have been purchased at a garage sale or thrift store (well, if it was purchased at a thrift store, it probably wasn't set up with fish in it...), or you may have inherited this aquarium from an old roommate who did not want to move it when she moved, or you may have gotten it from a friend, neighbor, or family member who no longer wanted the fish tank.

The Used Tank That Is Still (or Was Just) Set Up and Still Has Equipment - and May Come with Fish

I'll address this one first, mostly because I already wrote these instructions once. ;)

If the tank is set up, or has just been torn down, and still has all the equipment, you want to treat it like a tank you are moving with, especially if you are getting fish with this tank. If you are lucky, you can get some of the water that was in the tank and move it with you, to minimize the stress to the biological filter, fish, and plants.

I recommend you follow my recommendations for moving your aquarium to get a used tank of this sort up and going in your home.

The Tank That Was Just Up and Running, but No Longer Has All the Equipment

Sometimes you get a tank that was just up and running, but either you only purchased the tank, or the previous owner disposed of (or is otherwise using) the equipment that was being used on this tank.

In this case, you probably want to take the tank home and rinse it thoroughly with cool, running tap water, as this will remove any debris left in the tank. You may also want to wipe the tank out with a clean cloth.

Once you have done this, you will want to follow my recommendations for setting up your aquarium or upgrading to a larger aquarium as appropriate to get your new tank up and running.

Remember, it is very important that you not use any cleansers, solvents, detergents, perfumes, or other harmful chemicals when rinsing out the used tank, as these can leave residue that may remain in the tank long-term and could cause significant problems for your fish in the long run.

The Used Tank That Has Been in Disuse for an Unknown Amount of Time

If you have purchased an aquarium that has been unused for a long time, or if you are pulling a tank out of your own storage after a long period of disuse, the first thing you will want to do is check the tank for leaks. This will greatly reduce the risk that you will set up your tank and then meet the disaster of a leak or spill in your home.

Once you have leak tested your aquarium you will want to clean it.

In most cases, you can just rinse the tank with cool, running tap water to remove any debris, and then wipe it out with a clean cloth. If your tank has already been sitting for several days with some amount of water in it while you were checking for leaks, then probably almost any debris that was in the tank has had a chance to soak loose and will probably wipe away easily.

Often people are concerned about lime, or hard water deposits, on the glass in tanks that have been unused for more than a couple of days. Generally, you should not have to worry about these. If you have been through your leak testing for several days, you have probably noticed that these water deposits become translucent very quickly, and will almost always become clear over a few weeks under water.

Once you have rinsed the tank out, tested for leaks, and wiped it off, you should be ready to set up the tank.

I would recommend disposing of any filter media, or anything highly porous or with a high surface area, such as aquarium gravel and some decorations. You probably also want to dispose of any plastic that may have become brittle over time. All of these items should be replaced with new, because some of them will no longer be usable, and others may have been exposed to harmful to toxic chemicals that will be difficult or impossible to detect and remove.

If you purchased a used filter that requires cartridges or special media with your used aquarium, check with your local pet store to see if they stock the media for that filter and either pick up replacements or select a replacement filter that they stock the cartridges for.

Otherwise, make sure you rinse all your equipment thoroughly with cool, running tap water, and you should be ready to get your used tank up and running. I suggest you follow my recommendations for setting up your aquarium or upgrading to a larger aquarium as appropriate to get your used tank up and running.




"Thanks for your help. I feel less guilty. The past two weeks have been very educational for me regarding fish."
June 13, 2003
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"Thank you very much for all your useful information on your website. It really has helped us a lot. "
September 12, 2007
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