Published on 27-07-2019
A sump is a container placed below an aquarium, where filters, heaters and substrate are kept.
Water passes through the sump, where it gets filtered and heated. You can design your own sump, so you may choose what equipment to keep in it.Water comes down from the tank through a pipe and, after it passes through the sump, is sent back to the tank through another pipe using a water pump.
Open Systems and Closed Systems
Wherever the water flows from the tank is called a ‘system’. For example, if a tank has a hang on back filter and a sump, the water will flow inside the filter as well as the sump, before returning to the tank. In this case, the tank, sump and filter are all part of the system.
When water does not have any space to leak or escape the system, such a system is called a closed system. Essentially, this means that the water is continuously circulated through the system again and again using pipes and pumps. The water is isolated from the outside world. For instance, Fluidised bed filters are closed systems, as they suck in water through a tube, filter it and then return it to the tank using another tube.
When the water is open to the air, or there is an outlet for water to escape, such a system is called an open system. For instance, trickle filters are open systems, as the water is accessible even while being filtered. You can design a sump to be either open or closed, depending on your requirements.
Basic design of a sump
The aquarium has an overflow pipe, through which water is sent to the sump. This is the inlet pipe for the sump. This pipe sends water into the first chamber of the sump, where the heater is located. The water gets heated and fills the first chamber up. Then, it overflows into the second chamber, where the filter is located. Here, the water is filtered and then it overflows into the third chamber, where the biological filter media is present. Over here, bacteria are present that break down the waste into less harmful substances. Then, the water is sent back into the tank using a water pump and an outlet pipe.
As you may have noticed in the drawing, the partition between the first and second chambers is shorter in height than the sump itself. The partition between the second and the third chambers is even shorter. This is to ensure that the water flows properly from one chamber to the next, without risk of overflowing any one chamber.
This is just an example. You can have as few or as many chambers as you want. You can also shuffle the order in which the equipment is placed in the sump. You can design the sump to be cheap to build and run, while being easy to maintain.
Size of the sump
If there is a power failure, the water pump will stop working. So, all the water inside the outlet pipe will flow back down into the sump. The inlet pipe, which drains water from the tank into the sump, will also continue to drain the water until it drops below the overflow pipe level. The sump should be large enough to accommodate all this extra water, otherwise it will overflow and water will be wasted. This will also be dangerous as it can cause someone to slip, and because there are so many machines around, risk of electrocution will also be there.
To find out if the sump is big enough, just set everything up, let it run for about an hour and then shut off the power. The water level in the sump will rise, as the water from the inlet and outlet tubes will empty into the sump. After they are both emptied, if the sump has not overflowed, you are good to go. Now turn on the power and keep it running for about an hour. The water level in the sump will go back down. Mark this level with a waterproof tape. Whenever you replace water in the system, be sure not to exceed this level. Because if you do exceed the level and the power fails, the water will spill over from the sump onto the floor.
The benefits of having a sump
All equipment can be moved to the sump, where they will be safe from the fish. Large and aggressive fish such as Cichlids and Tankbusterscan attack the equipment, which can damage them. Broken equipment can even hurt or electrocute the fish. So the fish and the equipment can be kept away from each other, keeping them both safe.
Large equipment can be housed inside sumps, keeping them away from the line of sight. This will give your tank a cleaner look.