What Is An Aquarium Sump?

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What Is An Aquarium Sump? Most aquarium hobbyists, I think, have had a simple tank at some point, like a Petco tank with a simple filter and a heater. The first saltwater reef tank I had was a 46-gallon glass bowfront tank with a hang-on back filter, a heater, and a little maxi jet pump that ran on electricity.

I was introduced to the concept of a “sump” as I grew more engaged with online forums and met other reefers. I was intrigued by it and wanted to put it in place as soon as possible. We’ll talk about what an aquarium sump is and why you should use one in this article. It might be used successfully in both saltwater and freshwater aquariums if utilized correctly.

What Is An Aquarium Sump?

A “sump tank” or “sump” is just another tank that is below or at a lower level than the main aquarium. For the purposes of this post, we’ll assume it’s constructed of glass or acrylic. It’s possible that Rubbermaid tubs or other plastic containers could be used as a sump, but for the sake of this post, let’s assume that they are not.

A pump in the sump pumps water from the sump back up to the display tank to keep the right amount of water in each tank. So, all we’re after is a balance where water flows in and out of the aquarium display without overflowing it or the sump tank.

How Does Water Travel From The Sump To The Aquarium And How Is It Balanced?

As previously said, the water flows down to the sump using the most reliable of all methods–gravity! The concept of an overflow is presented here and should be briefly addressed. In an aquarium, an overflow is a box-like compartment that can be built into the tank or attached to the back as a “hang on back” device. A bulkhead fitting is utilized in this box, and PVC or other forms of tubing are used to convey water down to the sump.

Slits or “overflow teeth” on the top of the overflow box will suck water from the top 1′′-2′′ of the display aquarium. The water must now flow back up to the display tank, which is accomplished with an aquarium pump, sometimes known as a “return pump.” As long as your piping is large enough, the gravity feed will equal the gallons-per-hour rating on the pump (GPH) (head pressure needs to be calculated as well and is provided by the pump manufacturer). In other words, the pump’s strength determines the speed at which the water flows.

It’s usually a good idea to place a check valve on your pump to prevent a water siphon from the display, and only fill the sump halfway or lower so that water may flow down when the power goes out without overflowing the sump.

what is an aquarium sump

1. Sump Benefits Include Removing Eyesores From The Display

My displeasure with gazing at the equipment inside the aquarium display was one of the main motivators for installing a sump. My first 46-g reef aquarium included a heater, a hang-on back filter, and a circulation pump in the display, along with electrical connections visible in the aquarium. If you’re reading this, I’m guessing you agree!

So, once you’ve installed a sump, the heater(s) might be moved into it. To reduce the use of circulation pumps, I installed a “sea swirl,” which channeled water from the sump to various regions of the display tank. The unsightly component of the hang-on rear filter was also gone. Combine all of this with a black background in the tank, and any nozzles that remain are barely visible.

2. The Advantages Of A Sump Include The Elimination Of Surface Muck

Another thing that bothered me about my first reef aquarium was the oil and sludge that accumulated at the water’s surface – it was an eyesore and gave the tank a “dirty” appearance. The overflow box took care of this problem immediately when I added a sump to my setup, skimming the water surface 24/7 and sending all the crude and oil down to the sump to be filtered out.

3. The Advantages Of A Sump Include Improved Filtration

This means that we can now skim the surface of the water so that we can move it into a filter pad or filter sock so that we can get rid of waste. This is far more effective than using a hang-on back or a canister filter to lower the water level in the display.

4. The Advantages Of A Sump Include Increased Oxygen Levels

Because gravity causes water to “crash” into the sump, oxygen is introduced to the water, which is always a good thing. A protein skimmer, as described in the preceding section, will not only provide excellent filtration but also sufficient oxygen for the aquarium. This new source of oxygen will also assist you in maintaining healthy PH levels.

5. Sump Benefits Include Increased Water Volume

Another wonderful advantage of a sump that is frequently neglected is the increased water volume. Bigger is better when it comes to aquariums, and this is true since larger water volumes allow for more stability and less fluctuation. A larger volume can also accommodate more trash than a smaller one.

Let’s pretend you have a 100g tank with no sump. A power outage occurs while the aquarium is closed for the day while the owner is out of town. If creatures begin to die, the aquarium is now vulnerable to an unsafe increase or fall in temperature (depending on the season), and an ammonia surge is unavoidable. This is how it would look if there was a 30g sump instead of a 20g sump: The higher water volume would take longer to cool or heat and could hold more waste because there are fewer fish in the water.

Final Thoughts

There are numerous advantages to adding a sump to your existing aquarium setup or when constructing a new aquarium, as we’ve discussed in the sections above. We strongly suggest it and are convinced that it will be beneficial. If the budget allows, an acrylic sump is an ideal option because it can be readily adjusted and drilled. In addition, as discussed in prior articles, an acrylic sump is safer to use. I hope you found this post to be helpful and instructive in setting up a sump for your aquarium.

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