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Aquarium Sump Size Calculator

Aquarium Sump Size calculator

Choosing the right sump size, style, and layout is important to the success of any reef aquarium. But how do you calculate the size of your aquarium sump?

To figure out the number of gallons of room you should have in your aquarium sump, measure how much the level of water in the tank will decrease (in inches) after a power failure, and multiply it by the area (length x breadth) of the aquarium, and divide by 231.

In this article, we will look at what aquarium sumps are, why they’re useful, as well as what sump size you should choose depending on the capacity of your aquarium.

What is an aquarium sump?

An aquarium sump is a separate container or receptacle that is normally housed within the aquarium base. Water from the aquarium circulates to and from the sump. Sumps give extra area for concealing filtration gear and increasing the amount of water to aid with water stabilization.

An aquarium sump can be as basic as a one chamber receptacle or as complex as a tank with numerous compartments, each with its own function.

How does an aquarium sump work? 

Sumps operate by directing water from the primary aquarium via a sluice gate and overflow portion toward the sump. The water is then pushed back up towards the primary aquarium after passing through all the sump’s filtration and other equipment.

Water flow doesn’t stop as long as the ‘Return Pump’ is turned on. When the water is pushed again into the primary aquarium, it runs through a sluice gate and enters the overflow area. This mechanism maintains the primary aquarium’s level of water. It is then pushed back into the primary aquarium after draining into the sump.

Consider it similar to the overflow drain found in every wash basin. When the water level in the basin becomes too high, it flows into the hole and into the drainage pipe.

This is the way the sump apparatus operates. Rather than going to the waste treatment facility, the water runs into a container underneath the sink, is purified, and then reinjected from the faucet.

What are the benefits of an aquarium sump?

The following are the benefits of installing a sump in an aquarium

Equipment stays hidden

Nothing is more frustrating than admiring a gorgeous aquarium only to be distracted by wires, pipes, and devices dangling from every side of the tank. 

Algae remover

An aquarium sump enables you to place equipment such as Algae Turf Scrubbers or Refugiums to cultivate algae away from your primary aquarium instead of having it spread throughout it.

An increased amount of water

By installing a 20g gallon aquarium sump in a 50gal reef aquarium, the overall water capacity has grown by 40%! This can significantly aid in the stabilization of water levels.

More filtration

A sump provides a greater area for extra filter material to assist manage factors such as phosphates and nitrates. Chemical material can be put in media reactors or plastic baggies that dangle from the sump’s sides.

Larger equipment

Filtration gear comes in a variety of sizes, and if you are restricted as to how big a filter you can comfortably place inside your reef aquarium, your choices will be limited. Having an aquarium sump gives you more options for filtering apparatus.

What size sump do I need for my aquarium?

To figure out the number of gallons of room you should have in your aquarium sump, measure how much the level of water in the tank will decrease (in inches) after a power failure, and multiply it by the area (length x breadth) of the aquarium, and divide by 231.

Read on for some typical sump sizes based on the capacity of your reef aquarium.

How big of a sump do I need for a 100-gallon tank?

A 40-gallon sump is a decent size for a 100-gallon tank. Although a 30g capacity sump would suffice, a bigger volume will allow you to place equipment including heaters, skimmers, skimmer pumps, and so on. It all depends on what you’d like to set in it and the way you arrange it.

How big of a sump do I need for a 180-gallon aquarium?

When it comes to aquarium sump pumps, a larger capacity is usually better. With a 180-gallon aquarium, a 100g sump would be ideal. In any event, for a sump to function successfully, it must be capable of containing all of the water that drains to it as soon as the aquarium pumps are turned off.

How big of a sump do I need for a 75-gallon tank?

The general principle for veteran reef keepers was that the volume of the aquarium sump should be approximately 25% of the volume of the aquarium. According to this principle, a 20-gallon sump should be enough for a 75-gallon tank, but a 36″ long 29 will provide more room.

As previously said, the bigger the refugium/sump, the greater the net amount of water in the tank and a more decent area to hide equipment like your skimmer pump, heater, and so on.

Where should I install a sump for my aquarium?

Most fishkeepers put their aquarium sumps in one of these three areas in their houses:

  • Inside the aquarium stand
  • Behind the aquarium in a different room
  • In the basement underneath the aquarium

Inside the Aquarium Stand

This is definitely the most preferred place for many aquarists owing to the convenience of piping and the fact that it is neatly concealed as soon as the aquarium stand doors are shut. There are some seriously amazing sump setups out there, and it’s always amazing how much gear can be stuffed onto a stand.

Behind the aquarium in a different room

By installing the aquarium sump in a separate room behind the reef aquarium, you have a blank slate to plan the design, the freedom to add as much gear as you want, and the ability to add more apparatus afterward as your abilities and aquarium improve.

In the basement underneath the aquarium

If your house and money allow for it, this is a useful solution. It does not really cost extra, but having additional room and all the equipment installed at a comfortable working level has quite an effect on upkeep.

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