BASIC Sump Design - Illustrated

  • This thread is a thread designed for people entering this hobby, it is by no means the be all and end all of sump designs.

    I am also not going to argue the merits of this vs dozens of other sump options.

    One of several accepted sump design concepts that is often recommended on MASA is the so called 3 chamber Skimmer DSB Return sump. This thread is an attempt to answer new members questions on how to implement THIS design.

    Before you choose to go with this Sump design, it is your obligation to research the filtration and understand what each element of the sump does and whether an alternative filtration system may perform better for you... with that in mind before you choose this design make sure that you have read up about the following as a minimum and have decided that these systems are not for you at this stage or decide how you would like to incorporate these systems into the 3 chamber system

    ATS, Zeo, De-Nitrifyer, NP reducing Pellets, Bio Balls, macro Algae, carbon phos remover etc etc etc .......

    Right now that that is out of the way, lets design a 3 chamber Skimmer, DSB and return Sump.

    First off the sump should be as big as you can make it .....

    Chamber 1 is the Skimmer Chamber ..... the size of this chamber is dictated by either the size of your current skimmer or the size of a proposed skimmer upgrade.

    Chamber 3 is the return chamber and should be big enough to accommodate the return pump, usually this chamber can also host a chemical filter such as a carbon filter.

    Chamber 2 is simply the biggest that it can be, and must be able to have a sand bed of at least 15cm in depth, preferably 18cm.


    the image above is the basic basic sump and would work regardless of any additions, the additions i am going to suggest below are add ons and are not strictly required.


    A small box where the water enters, this helps to keep the detritus in suspension.


    A DSB works best with laminar flow, this deflection plate helps to stop turbulance over the DSB

    When deciding on the height of the divisions bear a couple of things in mind, the water must flow from chamber 1 to chamber 3 hence the height of the divider bewteen chamber 2 and 3 should be lower than between chamber 1 and 2. Distance Y should be at least 15cm and preferably 18cm, Distance X should be at least 5cm longer than distance Y even more if you are considering running macro algae on top of the DSB


    An RO resivoir can be added as a 4th chamber, in any configuration, shown here is a 4th chamber at the back, the float switch controlling the water level should be in the return water chamber (3)


    two points to remember when constructing the sump, Your Skimmer must be able to fit through the Gap indicated by J. In order to prevent flooding in the case of a power failure, the volume of water contained within gap K (excluding the volume that the skimmer will occupy) must be greater than the volume that will drain out of the display tank. as a rough guide assume that 1cm of water will drain from your DT therefore multiply Length and width of your DT by each other and then by 1cm, convert to Litres and ensure this is less water than is accommodated in Gap K of your sump. Failure to do so may result in a grumpy wife.


    Cubes sometimes require a different shaped sump to the traditional rectangle sump, pictured above is a simple variation on the normal design, note that a small powerhead may be required to create laminar flow in this design.


    Often tanks are on stands with a wooden support in the middle, simply connecting 2 smaller sumps with 2 x 50mm pipes will achieve the same result as a standard sump.

    Guys note once again I am not saying this is the ONLY way to build a sump, it is one of the ways and simply meant to answer a question that seems to continiously be asked by new members.