Glass aquariums were once made with stainless steel, aluminum, or plastic frames, but these have largely disappeared from the market and you will not find them in pet shops.
If you should be given such an old-fashioned framed glass tank, seek advice on how to clean it thoroughly and seal all the joints with silicone. Plastic aquariums are generally available only in very small sizes. They break and scratch easily, and the plastic walls often distort the image of the fish.
They are not recommended. You can, however, consider purchasing a small, inexpensive plastic tank to use as a quarantine tank when you need to isolate a diseased or injured fish for a short period of time.
Use the calculator in the form below to get your fish tank volume (US gallon or liter) by measuring the dimensions of your aquarium.
Aquarium size
The size of your aquarium depends on where it will be located and on the number of fish you wish to keep. Your fish are going to need as much room as you can possibly give them.
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A general rule of thumb commonly used to determine how many to put in an aquarium is 1 inch of per gallon (about 2.5 cm Of fish per liter) of water.
Use this rule for young fish no more than 2 inches (5 cm) long, and be sure to include the length of the fins. Once the fish begin to grow, the rule no longer really applies, some fish are heavy-bodied creatures that consume more oxygen per unit of length than fish having a more streamlined shape.
The slimmer species are probably the ones the rule was created for. In other words, keeping ten 1-inch (2.5-cm) fish in a 10-gallon (40-liter) aquarium will not allow much room for growth.
This does not mean the fish will not grow, it merely means they will not reach their full potential size, and their fins and bodies may not develop into the most beautiful or desirable proportions. Stunting could also mean the fish may not be able to breed well.
Five young fish, each 2 inches (5 cm) long, would initially be ideal for a 10-gallon (40-liter) aquarium. After a while, though, when the fish grow to 3 or 4 inches (7.5 to 10 cm), they will be a bit crowded. So if you want to keep five fish, you would probably be better off starting out with a 15 to 20-gallon (60-80 liter) aquarium.
You see, therefore, that the size of the tank you buy depends on the number of fish you wish to keep.
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