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Fish Bowl and Small Fish Tank Maintenance

Care of Small Aquariums, Vases, Urns, or Buckets

(The First Tank Guide)

What Is A Small Fish Tank?

A small fish tank is any aquarium under ten gallons (about 39 liters) total capacity.

A fish bowl is any container you are keeping fish in that is not filtered.

Remember, both of these apply, regardless of the shape of the container in question, or the materials the container in question is made from.

If your fish tank is either under ten gallons in total capacity or is not filtered, it is a small tank or bowl and should only be considered by experienced aquarium keepers who understand the drawbacks and disadvantages of such an environment for pet fish, and are willing to take on the extra challenge and additional maintenance required for these small aquariums.

Because of their small size and frequent lack of filtration, small fish tanks and fish bowls require a great deal more maintenance than a larger fish tank that has a reasonable probability of becoming - and remaining - stable.

Small Aquarium Maintenance

While a larger aquarium, once cycled, will only require a 10-15% water change once a week, a smaller aquarium requires much more work than that to provide a tolerable environment for your fish.

If your fish tank is under ten gallons in total capacity, even if it is filtered, do not expect it to remain stable and healthy. You will need to perform 50% or larger water changes at least twice a week, but preferably every other day. Without these massive and frequent water changes, it is likely that the tank will destabilize and put your fish in a worse position.

Remember, with these water changes it is still important to vacuum the gravel along with the water changes to remove debris from the gravel and help to maintain water quality.

Fish Bowl Maintenance

Fish bowls are slightly different from small fish tanks. Primarily, since a fish bowl does not have filtration (see the definitions above), a fish bowl is only a septic tank collecting the fish's waste and making the fish soak in it.

When you look at it with that in mind, you can see why most people consider fish bowls to be unduly cruel to any fish. However, you may already have the bowl, or it may have been given to you as a gift with the best intentions. In either case, you have an obligation to make the best of the conditions until you can get a healthy environment for your pet fish.

So, with your fish bowl, you want to do a 50-100% water change daily. This will remove the waste from the water on a frequent basis, reducing the fish's exposure to this toxic material.

With this, as with any other aquarium cleaning, it is vitally important to clean the gravel with each water change to remove any collected debris, solid fish waste, or uneaten food.

Aren't Those Massive Water Changes Stressful to the Fish?

Well, yes, large water changes like this are definitely stressful to the fish in question. however, the stress of these massive water changes is less problematic than the stress of being in such a small environment, whether it is a small fish tank or a fish bowl, without the large water changes.

Also, the more frequent the water changes are, the less important it is that the water changes be small. By keeping the frequency of these water changes high - at least twice a week for a small fish tank with a filter and at least every other day for a fish bowl without a filter - the stress of the water changes is significantly mitigated.

How do I Reduce My Fish Bowl Maintenance?

There are several things you can do to reduce the care requirements of a bowl.

First, get a top for the bowl. Having a top on your bowl reduces water loss due to evaporation and reduces the amount of debris that collects in the water from the environment. Tops are available for many sizes of bowls and most small tanks.

Second, get a filter for your bowl. There are box filters (both powered and unpowered), sponge filters, and under gravel filters available that are small enough for fish bowls. Most people find the sponge filters and corner filters to take up too much room in their bowls, and opt for the under gravel filters.

If you are using a filter in your bowl, remember that the filter will need maintenance as well, and should be cleaned or have cartridges changed regularly. For an under gravel filter, this means either vacuuming the gravel when you do water changes or stirring up the gravel to free the debris caught in it so you can remove this debris when you do your water changes.

Third, agitate the water in the bowl. This can easily be done with a small water pump or an air pump. This will make excess food and other debris more visible so it will be easier to tell if you are over feeding your fish or if there is other debris collecting in the bowl. This also makes it easier to see the debris in the tank so you can more readily remove it when doing your water changes. Additionally, this increases the surface area greatly, improving gas exchange. In most cases, having a filter in your bowl agitates the water sufficiently.

In a bowl where you have provided maximized surface, are agitating the water and providing filtration, and have the bowl covered, water changes can usually be reduced to twice weekly. However, remember to watch your fish for signs of ammonia stress (gasping at the surface, lethargy, loss of appetite, loss of color, and inflammation of the gills, eyes, and possibly fins) or excess debris in the water, such as fish waste or uneaten food, and perform extra water changes as necessary.

Remember that even if you take these precautions, and make an effort to make the small aquarium or fish bowl a better place for your fish, you still have not overcome that small water volume issue, which is the primary problem with these fish tanks. Adding a filter or agitating the water will not significantly reduce the maintenance these small aquariums require.

Also keep in mind that purchasing all the equipment you really need for your small fish tank or fish bowl will likely cost you more than getting a ten gallon aquarium with the proper equipment would have in the first place.

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