If it’s your first time buying an aquarium, tank dimensions need serious thought. In addition the overall size and shape of an aquarium, you need to think about internal capacity to work out how many fish you can comfortably keep at any one time. Once you’ve settled on a tank of a certain size, you can also work out how much it is going to weigh once filled with water and stocked with plants and fish. Experienced aquarium owners tend to go for custom-made tanks with unique shapes. However, the beginner is best purchasing a ready-made tank model with more standard dimensions.
Standard Aquarium Dimensions
If you’re looking to buy a basic aquarium model, your best bet is a so-called standard tank. These tanks are rectangular in shape, with glass sidings and plastic bases. Additional plastic rims will provide the tank with reinforced support. Most standard tanks are made from tempered glass, although this glass is rarely thicker than 0.5 inches. If you’re looking for a particularly large rectangular tank with a more substantial capacity, you’ll probably notice that suitable models will include support rails in the middle of the tank to help everything hold together.
All standard tanks are measured from the outside, along the external plastic base. Standard tanks with a capacity of 45 litres tend to have a width of 20 inches, with a depth of 10 inches and a height of 12 inches. This can vary slightly between brands, but the difference will be minor. When filled with water and substrate, the overall weight of these tanks will be approximately 50 kilograms.
Although 45-litre tanks are by far the most common, they are not the only standard aquarium sizes. If you’re looking for a smaller tank, there are two main options. The smallest commonly available size is the 2.5-gallon tank, which works out to around 11 cubic litres. These small tanks have a width of 12 inches, a height of 8 inches and width of 6 inches. When filled with water and substrate, these tanks will weigh approximately 12 kilograms.
Another compact aquarium option is the 5-gallon tank. These tanks house around 68 cubic litres of water. Tank dimensions are fairly generous, with a length of 16 inches, a depth of 7 inches and a height of 10 inches. When filled with water and substrate, the overall weight of these tanks is around 28 kilograms.
If you’re looking for a larger tank model, a 15-gallon aquarium is a good choice. A standard 15-gallon tank will house approximately 68 litres of water. These tanks measure 24 inches in length, with a depth of 12 inches and a height of 12 inches. When filled with water and substrate, the overall weight of these tanks is approximately 50 kilograms. The 15-gallon tank also comes in a taller version. The dimensions and weight credentials of these tanks are much the same as a standard 15-gallon model, although the tank height is 18 inches, rather than 12 inches.
Larger Aquarium Sizes
Although compact tanks are ideal for smaller spaces, most people will prefer a larger option. To encourage active routines and ensure your plants and fish remain healthy, you should really be looking for a much larger thank the compact models previously described. A 20-gallon tank is a good starter option. These tanks are available in high and long models, with the high model measuring 24 x 12 x 16 inches. These tanks can house up to 91 cubic litres of water. When fully filled with water and substrate, these tanks will weigh in excess of 100 kilograms. In addition to these tank sizes, 25-gallon and 29-gallon aquariums are also popular choices.
If you’re looking to go even larger, a 30-gallon tank is a good option. These aquariums are a good option for those looking to breed fish, as they provide sufficient space for a growing aquatic population. In addition to providing capacity for around 113.5 cubic litres of water, these tanks measure 36 x 18 x 12 inches. When filled with water and substrate, the overall weight of these tanks can exceed 170 kilograms.
Another option for fish breeders is a 40-gallon tank. A standard long version of this tank can house 181 cubic litres and measures 42 inches by 12 inches, with a vertical height of 16 inches. When filled with water and suitable substrate material, these breeder tanks can weight more than 200 kilograms. If you opt for a particularly heavy tank, you will almost certainly need to incorporate a load-bearing stand as part of your aquarium setup.
Choosing a Suitable Aquarium Size
Before you settle on a tank size, you need to mull over a few factors. Although many novices assume a compact tank will be a better fit, this is not always true. In fact, a larger tank is often easier to clean and maintain. With more room to work with, you can rearrange plants and maintain substrate without disturbing the internal conditions of your aquarium too much. A larger tank also means you can add significant numbers of fish without worrying about overcrowding. More cubic litres of water also means that dangerous nitrate and phosphate levels will take a while to build up, which is beneficial to the novice aquarist.
Ultimately, available space will determine how large you can go with an aquarium. You will need a suitable indoor space that can comfortably house an aquarium, as well as provide additional space for filter hosing and other equipment.
Weight Factors
You also need to think seriously about weight. No two aquariums will ever weigh the same once filled with water, substrate, fish and plants. If you need to purchase a stand, always opt for one with a higher load-bearing capacity than what you think you’ll need.
Substrate is one of the major factors that will determine the overall weight of your aquarium. Generally speaking, you will need to incorporate half a kilogram of substrate material for every 4.5 litres of water you are adding to your tank. This ratio will help you calculate how heavy your aquarium is going to be, prior to actually setting it up. However, different substrate material will contribute varying amounts of weight to your aquarium.
That being said, don’t assume that fine gravel and sand will weigh less than larger gravel substrate. In most cases, you will have to apply more of this fine grain material to your aquarium to achieve desirable coverage. Of course, water also adds considerable weight to an aquarium. Not all types of water weigh the same, with saltwater weighing slightly more than freshwater because of its sodium and mineral content.
The fish you keep in your aquarium will also add their own weight into the mix. Freshwater fish tend to be smaller and therefore lighter than their saltwater counterparts. If you’re interested in keeping nano fish, you can introduce large populations to your aquarium without worrying about adding considerable weight to your aquarium and stand. However, certain fish species require more living space than others.
This is especially true of fish varieties that prefer to shoal and remain in large groups. Certain fish breeds like neon tetras might be small, but they can only thrive as part of large groups of a dozen or more fish. Certain types of guppies however, will only need to be paired up with two or three tank mates, making them suitable for smaller aquariums.
Final Thoughts
If you’ve got a large budget, it can be tempting to invest in a custom-built aquarium. However, calculating weights can be difficult with these bespoke designs. To make your life easier, go for a standard aquarium size with regular dimensions. This will allow you to calculate how much water you will need, how much substrate material you will need to purchase and how many fish you can realistically keep at any one time.
