PUMP FED INSTALLATION
-6-
It important that on the return line back to the pond there is no section of pipe
where the pipe rises then falls as airlocks will form in this section stopping flow an
example of this is shown in Figure 4.
When installing a pump fed Nexus
there is a maximum height difference
that the Nexus base can be below
the pond water level also shown in
the Fig 6. This height is dependant
on the distance between the Nexus
and the return point to the pond,
the table below shows the maximum
heights and distances when using 4” (110mm) pipe.
Important: Essential Action
For Pump fed units it is important that you get the height of the outlet standpipe
correct. The height of this standpipe is very important as it controls the height that
the outer biological chamber of
the Nexus runs at. For a standard
Nexus installation you need to
cut a length of your 4” (110mm)
return pipe: 21” (535mm) for a 200
and 23.2” (590mm) for a 300. This
needs to be inserted into the exit
chamber (E) through the outlet
(F) and then secured using the
4”-4” (110mm) (Fig 1.1) rubber
boot leaving 2” (50mm) below as
shown in Fig 7. 2” (50mm) of pipe
below the boot will allow you to
connect any fitting onto your
Nexus such as a valve, elbow or
straight connector. To check that
you have the height of the outlet
pipe correct you can measure
from the top of the standpipe to
Fig 6
Max distance (H) below water
level of Nexus base
Nexus 200
Nexus 300
Next to Pond 350mm
14”
500mm
20”
Within 5m
100mm
4”
250mm
10”
Over 5m
At or above water level
Fig 7
Fig 8
