Parts of the Durso Standpipe

The bottom section:

If you have a threaded bulkhead, the first fitting is a 1 inch threaded male adapter which screws into the threaded bulkhead. Be sure to use Teflon tape on the threads, you want this to be a water tight seal.  Note: A male adapter is only needed for threaded bulkhead.

Next, convert the 1 inch pipe to a 1 ¼ inch pipe using a reducer bushing. (There is a small section of 1 inch PVC pipe linking these two parts). The reducer bushing is then inserted into a coupling. 

• If you have access to a reducing male adapter that is a good option to use -- It is 1 inch male by 1 ¼ inch insert fitting. Threaded style Durso Standpipes purchased from me will use this fitting. 
• If you have a slip bulkhead then see if you have can get a reducing coupling -- It is 1 inch insert by 1 ¼ inch insert fitting.  Slip style Durso Standpipes purchased from me will use this fitting.

The middle section:

Then the vertical PVC pipe is inserted in the coupling. The PVC pipe I recommend is Schedule 26 commonly called thin-wall PVC pipe. It is thinner, lighter and drains better than schedule 40 pipe.  The height of this section of pipe varies depending on the parts you use and how tall your aquarium is.  The end goal is that when completed, the top end-cap will be about equal to the upper rim of the aquarium. 

I recommend PVC cement for this connection to keep it water tight.

The top section:

At the top of the standpipe is a 1¼ Tee fitting. This is attached to the standpipe with Teflon tape only. I suggest using about three wraps to get a good tight seal.  Do not glue this fitting.

A special elbow connector called a “Street-ell” or “Street 90″ is then inserted and pointed directly downwards. This is the water intake, it will always be submerged. Since it is submerged, it can not suck in surface air.

Note: A street-ell allows the ell to be inserted directly into the Tee fitting without requiring a separate small PVC pipe length to connect the elbow and tee together. A standard PVC Elbow can be used but may not be as compact as the street-ell. To fit into the older style small AGA overflows, just trim the street ell connector down. Only about ¼ inch is needed for a gluing surface.

Use PVC cement to connect the Street-Ell to the Tee. On the top part of the Tee fitting, insert a small section of PVC pipe which should be glued in. Finally place an End-Cap fitting to top the unit. The End-Cap is held on with teflon tape.