cajen
19-05-07, 22:31
Simple Sumps: design and installation
What is a sump?
A sump is a water container (usually a tank but it could be anything that holds water) which is connected to the main display tank and is generally hidden away in the cabinet.
Why have one?
The short answer is that a sump is never absolutely necessary: many successful and beautiful tanks don’t use one. There are, however, advantages:
Increases tank volume and thus water stability
Increases surface area and the water’s passage through the sump aids in gaseous exchange, helping to maintain pH levels
Allows equipment like the protein skimmer and heater to be hidden away, improving the natural look of the display tank
Can provide a quiet place where small animal life can shelter and multiply away from predation (a ‘refugium’ or a ‘cryptic zone’). These creatures are sucked into the display, providing a regular source of live food for the inhabitants
Provides a place where undesirable crabs, etc (which can come in on live rock) can be put
Can help with water quality (using algae and / or a deep sand bed).Any drawbacks?
Obviously, a sump means additional expense: apart from the sump itself you will need a return pump, piping and taps, but this is cheap compared with the outlay needed for the rest of the system! There may be an increase in noise from the added pump(s), overflows and returns, though it can be minimised (see below). It’s also one more thing to go wrong!
A simple sump installed in a cabinet
For smaller tanks and sumps, flexible pipework may suit; for larger setups rigid pipes are better.
In this example, the water from the display will flow into the right-hand chamber and is returned from the left:
http://www.ultimatereef.net/uploader/2006Q4/sump%201.jpg
The right chamber takes the flow from the tank and also houses the protein skimmer. The central chamber has the heater, some live rock and chaeto algae and is lit. (Note that the LR will benefit from a good through flow to avoid detritus build-up). The centre section can also house a deep sand bed. The left chamber contains the return pump back to the display. The pipe you see running from left to right increases the flow through the sump and allows the flow to the tank to be controlled with a valve:
http://www.ultimatereef.net/uploader/2006Q4/sump%202.jpg
How it works - the Flow
Water from the main display passes over a weir into an overflow chamber. The height of this weir determines the water level in the main display. The weir should consist of a plate with slots (teeth) to stop snails, fish etc entering the overflow chamber. Water in this chamber overflows either through a pipe drilled into the tank side, or into a standpipe mounted through the base of the tank, and flows down into the first chamber of the sump below.
There is a double baffle between the first and main chambers of the sump, so that water has to flow down and under the first baffle then up and over the second baffle. This acts as a bubble trap to stop any bubbles caused by the water falling into the sump from entering the main sump chamber.
The water level in the main sump chamber (and the first chamber) is determined by the height of overflow baffle into the final chamber. If desired, there may be a second baffle that the water flows under, again as a bubble trap.
Water is then pumped from this final chamber, up and over and back into the display tank. This causes the water level in the display tank to rise minutely, which overflows over the weir into the overflow chamber, and so forth - a dynamic balance is achieved.
Note: It is not possible to use 2 pumps, one pumping to a sump and one pumping back again as you will never achieve a flow balance and all the water will end up in one of the tanks. The overflow scheme is the only way.
Design considerations
The return pump has to pump water up hill to get it back into the display tank. This head of water means the pump has to work harder and it decreases the flow from the pump. Ensure that the pump you select has sufficient head capability and sufficient flow at that head of water.
The overflow pipe must be capable of handling all the flow of the return pump and a good margin more.
Be aware of potential flood problems:
If the return pump fails or there is a power cut, the display tank will empty slightly to the level of the weir plate, and the overflow chamber will empty to the level of outlet pipe or standpipe. Ensure that the sump has enough extra space to accommodate this extra water without overflowing.
If the overflow weir or outlet pipe gets blocked, the return pump will continue to pump water up to the display tank. However, by design, it will only empty the final chamber of the sump. Ensure that the display tank can accommodate this extra water.
If the outlet pipe from the return pump exits into the display tank under water (to stop the splashing noise) it can cause a back syphon if the pump stops. Drill a small hole in the pipe to act as a syphon break and ensure it is never blocked.
To minimise bubbles in the sump and to provide some mechanical filtration, a filter sock or a box containing filter floss can be put under the outlet pipe. Any floss should be changed at least once a week to prevent it from going biological and raising nitrates.
Top up water
The water level in the display tank remains constant at the level of the overflow weir. The water level in the sump remains constant at the level of the final baffle. So as water evaporates from the system, the water level in the final sump chamber will fall. RO water needs to be added daily to maintain a constant level in this chamber. If you have an auto-topup system then the control float needs to be in this chamber.
__________________
A simple sump design (thanks to Zimreef)
http://www.ultimatereef.net/uploader/2006Q4/skp-sump3.jpg
Note that these examples are simple designs. More sophisticated sumps can be seen on the sump thread (http://www.ultimatereef.net/forums/showthread.php?t=142521) .
Cajen and ~Tony~
_____________________
UR.com Team
Copyright © 2007 UltimateReef.com (http://www.ultimatereef.net/forums/showthread.php?t=190134)
What is a sump?
A sump is a water container (usually a tank but it could be anything that holds water) which is connected to the main display tank and is generally hidden away in the cabinet.
Why have one?
The short answer is that a sump is never absolutely necessary: many successful and beautiful tanks don’t use one. There are, however, advantages:
Increases tank volume and thus water stability
Increases surface area and the water’s passage through the sump aids in gaseous exchange, helping to maintain pH levels
Allows equipment like the protein skimmer and heater to be hidden away, improving the natural look of the display tank
Can provide a quiet place where small animal life can shelter and multiply away from predation (a ‘refugium’ or a ‘cryptic zone’). These creatures are sucked into the display, providing a regular source of live food for the inhabitants
Provides a place where undesirable crabs, etc (which can come in on live rock) can be put
Can help with water quality (using algae and / or a deep sand bed).Any drawbacks?
Obviously, a sump means additional expense: apart from the sump itself you will need a return pump, piping and taps, but this is cheap compared with the outlay needed for the rest of the system! There may be an increase in noise from the added pump(s), overflows and returns, though it can be minimised (see below). It’s also one more thing to go wrong!
A simple sump installed in a cabinet
For smaller tanks and sumps, flexible pipework may suit; for larger setups rigid pipes are better.
In this example, the water from the display will flow into the right-hand chamber and is returned from the left:
http://www.ultimatereef.net/uploader/2006Q4/sump%201.jpg
The right chamber takes the flow from the tank and also houses the protein skimmer. The central chamber has the heater, some live rock and chaeto algae and is lit. (Note that the LR will benefit from a good through flow to avoid detritus build-up). The centre section can also house a deep sand bed. The left chamber contains the return pump back to the display. The pipe you see running from left to right increases the flow through the sump and allows the flow to the tank to be controlled with a valve:
http://www.ultimatereef.net/uploader/2006Q4/sump%202.jpg
How it works - the Flow
Water from the main display passes over a weir into an overflow chamber. The height of this weir determines the water level in the main display. The weir should consist of a plate with slots (teeth) to stop snails, fish etc entering the overflow chamber. Water in this chamber overflows either through a pipe drilled into the tank side, or into a standpipe mounted through the base of the tank, and flows down into the first chamber of the sump below.
There is a double baffle between the first and main chambers of the sump, so that water has to flow down and under the first baffle then up and over the second baffle. This acts as a bubble trap to stop any bubbles caused by the water falling into the sump from entering the main sump chamber.
The water level in the main sump chamber (and the first chamber) is determined by the height of overflow baffle into the final chamber. If desired, there may be a second baffle that the water flows under, again as a bubble trap.
Water is then pumped from this final chamber, up and over and back into the display tank. This causes the water level in the display tank to rise minutely, which overflows over the weir into the overflow chamber, and so forth - a dynamic balance is achieved.
Note: It is not possible to use 2 pumps, one pumping to a sump and one pumping back again as you will never achieve a flow balance and all the water will end up in one of the tanks. The overflow scheme is the only way.
Design considerations
The return pump has to pump water up hill to get it back into the display tank. This head of water means the pump has to work harder and it decreases the flow from the pump. Ensure that the pump you select has sufficient head capability and sufficient flow at that head of water.
The overflow pipe must be capable of handling all the flow of the return pump and a good margin more.
Be aware of potential flood problems:
If the return pump fails or there is a power cut, the display tank will empty slightly to the level of the weir plate, and the overflow chamber will empty to the level of outlet pipe or standpipe. Ensure that the sump has enough extra space to accommodate this extra water without overflowing.
If the overflow weir or outlet pipe gets blocked, the return pump will continue to pump water up to the display tank. However, by design, it will only empty the final chamber of the sump. Ensure that the display tank can accommodate this extra water.
If the outlet pipe from the return pump exits into the display tank under water (to stop the splashing noise) it can cause a back syphon if the pump stops. Drill a small hole in the pipe to act as a syphon break and ensure it is never blocked.
To minimise bubbles in the sump and to provide some mechanical filtration, a filter sock or a box containing filter floss can be put under the outlet pipe. Any floss should be changed at least once a week to prevent it from going biological and raising nitrates.
Top up water
The water level in the display tank remains constant at the level of the overflow weir. The water level in the sump remains constant at the level of the final baffle. So as water evaporates from the system, the water level in the final sump chamber will fall. RO water needs to be added daily to maintain a constant level in this chamber. If you have an auto-topup system then the control float needs to be in this chamber.
__________________
A simple sump design (thanks to Zimreef)
http://www.ultimatereef.net/uploader/2006Q4/skp-sump3.jpg
Note that these examples are simple designs. More sophisticated sumps can be seen on the sump thread (http://www.ultimatereef.net/forums/showthread.php?t=142521) .
Cajen and ~Tony~
_____________________
UR.com Team
Copyright © 2007 UltimateReef.com (http://www.ultimatereef.net/forums/showthread.php?t=190134)