Guide
How much does a fish tank weigh?
By the Aquarium Calculator team
A filled aquarium weighs roughly 1.2 kg per litre of capacity (about 10 lb per US gallon) once the glass is included, before substrate and rock. A 60 L tank weighs about 79 kg full, a 200 L tank about 245 kg, and a 55-gallon tank about 266 kg (587 lb). Add 1.5–1.6 kg for every litre of gravel or sand.
Weights of common tank sizes
These figures come from the tank weight calculator, using plain glass at a typical thickness and filling each tank to the top with fresh water. For metric tanks: 40 L weighs about 48 kg full, 60 L about 79 kg, 100 L about 123 kg, 200 L about 245 kg, 300 L about 369 kg and 450 L about 545 kg. For US tanks: a 10-gallon weighs about 47 kg (103 lb), a 20 long about 88 kg (195 lb), a 29-gallon about 130 kg (287 lb), a 40 breeder about 208 kg (459 lb), a 55-gallon about 266 kg (587 lb), a 75-gallon about 368 kg (811 lb) and a 125-gallon about 544 kg (1,200 lb).
Empty, the same tanks are surprisingly light: the glass of a 60 L tank weighs about 16 kg and a 200 L tank about 45 kg. Almost all of the weight is the water, which is why a tank that two people can carry empty can need a reinforced floor when it is full.
What makes up the weight
Four things add up. Water weighs about 1 kg per litre (8.34 lb per US gallon); saltwater is about 2.5% heavier. Glass weighs about 2.5 kg per litre of glass, so thicker glass on tall tanks adds noticeably. Substrate is heavy: sand weighs about 1.6 kg per litre of bed and gravel about 1.5 kg, while lightweight aquasoil is about 0.8 kg. Rock, driftwood, equipment and the stand itself come on top.
Take a 100 × 40 × 50 cm tank of 200 litres. The water weighs about 200 kg and the 10 mm glass about 45 kg. A 5 cm bed of gravel adds about 30 kg, and a moderate rockscape another 10–20 kg. Running, the tank weighs close to 300 kg, all resting on 0.4 square metres. The tank weight calculator lets you add your own substrate weight from the substrate calculator for an exact total.
Choosing a stand
Use a stand built for aquariums and rated for at least the full running weight, not a bookcase, chest of drawers or shelf. Ordinary furniture is designed for a fraction of the load, and particleboard softens and sags over time if it gets wet. Steel frame stands and solid wood cabinet stands both work well; check the manufacturer's rating against the weight of your filled tank.
The stand must be perfectly level and flat. Any twist puts stress on the silicone seams and the glass. Rimless tanks are usually placed on a thin foam levelling mat or a flat board so the base is supported evenly, while framed tanks are designed to rest on their frame only, so follow the manufacturer's instructions. Check level in both directions before filling, and again after a week.
Will my floor hold it?
Small and medium tanks are fine on almost any normal floor. As tanks grow, the concern is the concentrated load on a small footprint. On upper floors, place larger tanks against a load-bearing wall and across the floor joists rather than parallel to them, so the weight spreads over several joists. Ground floors on a concrete slab can take almost any home aquarium.
As a rule of thumb, anything above about 280 litres (75 gallons) on a suspended wooden floor, or any tank in an old building or a rented flat, deserves a check by a builder or structural engineer before you fill it. It is a small cost compared with the damage a failure would cause.
Moving and filling safely
Never move a tank with water or substrate in it. Even a few centimetres of water adds hundreds of kilos of force on the seams when the tank flexes. Drain it completely, remove the substrate, and carry the empty glass by its base with at least two people.
When setting up, place the tank on its stand in its final position before adding anything, then add substrate, hardscape and water. Enter your dimensions in the tank weight calculator to get the empty and full weight before you buy the stand.
Check your own tank
Enter your real dimensions to get exact figures for your setup in a few seconds.
Open the Tank Weight