A 125 gallon aquarium is one of the most popular sized aquariums for hobbyists who want to have a large tank.
Knowing the exact dimensions of an aquarium is crucial when planning for the right location in your home or building a stand that will support it’s size and weight.
Technically, a home aquarium can be built in a variety of sizes. They can be custom built in glass or acrylic using any dimensions you choose.
If you are purchasing a standard size 125 gallon aquarium, they are generally built by a variety of manufacturers with the same dimensions.
The following information will show you the exact dimensions of a 125 gallon aquarium along with other important facts about an aquarium of this size.
What are the dimensions of a 125 gallon aquarium?
A standard size rectangular 125 gallon aquarium has dimensions of 72″ long x 19″ wide x 21″ tall. This includes the plastic trim around the glass. If the tank does not have a trim, these dimensions would be for the glass or acrylic edges.
These dimensions are for the tank only and do not include the cabinet or canopy, lighting, or other equipment.
Depending on the manufacturer, the trim size can vary slightly.
If you are looking for an aquarium to hold 125 gallons of water but have different dimensions, you will require a custom build from an aquarium manufacturer.
It’s possible to have a tank hold the same volume of water but have a variety of dimensions.
How much does a 125 gallon aquarium weigh?
Depending on the material used to build the aquarium, it’s weight can vary. Aquariums built using glass are much heavier than aquariums built using acrylic.
On average, a 125 gallon glass aquarium weighs 200 pounds. This weight is for the glass only. A 125-gallon acrylic aquarium weighs around 100 pounds which is half of the glass aquarium weight.
Over time, the weight of glass has become lighter. Many years ago, the glass used to build aquariums was very thick and heavy.
Today, a 125 gallon aquarium is still very heavy but not as much as it would have been 5 or 10 years ago.
Once you start adding equipment, decorations, and water to an aquarium, the overall weight will increase substantially.
A 125 gallon aquarium filled with freshwater will weigh around 1237 pounds.
The weight of freshwater is 8.3 pounds per gallon.
If you are planning to have a saltwater aquarium, it will weigh closer to 1268 pounds.
The weight of saltwater is 8.55 pounds per gallon.
An aquarium of this size and weight requires a heavy duty stand to support the weight.
How many people does it take to carry a 125 gallon aquarium?
If you are planning to carry a 125 gallon aquarium from one place to another, you will need 2 to 4 people to be safe.
While 2 people (one on each end) can lift the tank, keep in mind that the tank will be bulky and difficult to maneuver.
It’s important to never move an aquarium when filled with water.
How do you calculate aquarium volume?
To calculate the volume of aquarium water, you need the length, width, and height of the aquarium.
All aquariums are sold based on the volume of water it will hold. Either in gallons or liters.
Use the following formula to calculate an aquariums volume.
Length x width x height / 231 = volume of water in gallons
Using the dimensions for a 125-gallon aquarium simply multiply the numbers together and divide by 231.
72 x 19 x 21 = 28,728 / 231 = 124.36 gallons.
Regardless of the aquarium size, you can use this formula to calculate volume.
How many fish can you keep in a 125 gallon aquarium?
The biggest advantage of having a large aquarium like a 125-gallon, is you can keep larger fish and higher quantity than you can keep in smaller aquariums.
There is no set rule or requirements for how many fish you can keep in an aquarium.
It’s important that you provide enough space for the fish to remain healthy. Too many fish in a tank will cause many problems leading to a poor fish keeping experience.
A 125-gallon aquarium is 6 feet in length which is suitable for fish larger than 6 inches. You can keep a variety of small and large fish in the tank.
Depending on the tank size, some people will use a rule of 1 inch of fish per gallon.
But this doesn’t make sence for all tank sizes. For example, if you have a 10 gallon aquarium, you wont have a 10 inch fish.
But you could have 10 fish that are 1″ each.
A 55-gallon aquarium which has dimensions of 48″ long x 13″ wide x 20″ tall can hold around 10 fish that are less that 5″ each.
In a 125-gallon aquarium, you can easily keep 10 to 20 fish that reach 6 inches in size.
As the fish grow larger, you will need to reduce the amount in the tank.