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Pond Construction.
At some stage in the planning and design of a pond the decision of what type of construction method to use has to be made. The two common methods are Liner or Block built.
Whichever is used, a bottom drain or drains should be installed at the lowest point to ensure efficient removal of heavy solids into a gravity filtration system.
Putting a pump into a pond is a quick and easy solution to getting effective circulation and filtration, however it is unsuitable for fish ponds.

Bottom Drain sump type
Bottom drains are installed into both concrete and liner ponds at the lowest point. The dome cover prevents fish from getting into the pipe work.
Installation: the sump part of the drain and pipe connected to it are set into a trench in the bottom of the pond. the trench must be back filled and consolidated prior to a liner being installed. For concrete ponds the drain and pipework are

is installed in into a preformed trench, before being concreted into place.
See picture left.
Each drain is supplied with a loose flange ring. This is used to clamp the liner to the sump, a suitable mastic such as silicone or polyurethane must be used to seal the liner to the sump before the clamp ring is screwed into place.

The flange ring is not used in concrete ponds. The sump is installed so that the top edge is flush with the concrete. It is then epoxy covered or G4 or fibre glassed over. The height of the domed cover can be adjusted by trimming the internal support tube to the required length after the sump installation is complete.

Side Drains
These are used as mid level pond or tank outlets to the filter. They can also be used as bottom drains, however they are only supplied with a straight socket connection, so a bend must also be installed as well.
Supplied complete with snap on dome cover and loose flange ring with stainless steel screws.

Bottom Drain Sump type sizes:
56mm waste pipe size
63mm metric pressure
110mm waste pipe and metric pressure
4" imperial pressure
160mm waste pipe and metric pressure
6" imperial pressure

Air Ring
the air ring is an attachment for conventional bottom drains and it attaches to the domed cover, to convert it into an aerated drain but without having to go through major construction works.
Sizes available for 56/63 and 110mm drains.