Welcome

Medcalf Bros. Hy Flo
Vintage Reciprocating
Piston Air Pumps







*** All Models ***

*** For Sale ***



Manufactured by:
    Medcalf Bros.
    Cranborne Road
    Potters Bar
    England

We also provide:
    Servicing and Repairs.
    Spare Parts.
All enquiries :





Available for purchase : a wide selection of Hy Flo (HyFlo, Hy-Flo) pumps, originally manufactured by Medcalf Bros. Ltd. of Potters Bar, England...

Exquisite looking, near silent pumps - both functional and aesthetically pleasing - these remarkable show-pieces are a British design classic, and in recent years have become increasingly difficult to track down.

Out of production for close to three decades, still regarded as being light-years ahead of the competition.

Models available : "A", "B", "C" and "Junior" Hy Flo Pumps available including both aquarium and technical/laboratory pumps (please use the menu provided above to look at individual models).

Discounts are available for multiple purchases.

All pumps come with an instruction/maintenance sheet - available for download.

When available, we also have a limited number of spare parts for various models.

New Feature !! : reference list of all recorded pump plates with serial numbers.

New Feature !! : youtube videos of Hy Flo pumps, including a new service / maintenance video.


If you are unable to find the pump you are looking for, or just have a general enquiry, please feel free to drop us a line at:
and we'll get straight back to you.

We can also offer service and repair facilities - if you are experiencing a problem with your pump, again, just get in touch with us at : and we'll try to help.





!!! Latest Stock !!!
- Thursday, April 9, 2026 -



Boxed Model C
Model C pump with both air output and vacuum inlet components.
Excellent working order and lov... [click for details & full pictures]
[details]

Model C Aquarium Pump
Model C pump with dual output and vacuum inlet components.
Perfect working order and good condi... [click for details & full pictures]
[details]

Model C Aquarium Pump
Model C pump with dual output and vacuum inlet components.
Pump motor/coil emits low hum when r... [click for details & full pictures]
[details]

Model C Aquarium Pump
Model C pump with dual output and vacuum inlet components.
Perfect working order - poor cosmeti... [click for details & full pictures]
[details]

Model C Hy Flo Pump
Model C pump with dual output and vacuum inlet components.
In good working order with a fair am... [click for details & full pictures]
[details]

Model C Hy Flo Pump
Model C pump with dual output and vacuum inlet components. Pump has mis-matched pistons.
Pump ... [click for details & full pictures]
[details]

Electric Blue Model A Pump
Blue finish reconditioned Model A Hy Flo
Lovely condition condition.
Brand new Series IV p... [click for details & full pictures]
[details]

Model B laboratory pump
Model B laboratory pump in excellent condition with dual output and vacuum inlet components - very m... [click for details & full pictures]
[details]

Model B Aquarium Pump
Double piston, four outlet model B aquarium pump.
Excellent runner, with minor cosmetic loss to... [click for details & full pictures]
[details]

Model B Laboratory Pump
Dual piston laboratory pump.
An excellent runner, with both vacuum and air components.
In ... [click for details & full pictures]
[details]

Model B Technical / Laboratory Pump
Dual piston laboratory pump.
An excellent runner, with both air and vacuum components.
In ... [click for details & full pictures]
[details]

Model B Technical / Laboratory Pump
Dual piston laboratory pump.
An excellent runner, with both air and vacuum components.
In ... [click for details & full pictures]
[details]

Boxed Model A Aquarium Pump
Single piston twin outlet model A aquarium pump.
Excellent runner in lovely condition, with ori... [click for details & full pictures]
[details]

Model B laboratory pump
Model B laboratory pump with significant paint loss to the pump shell and some minor loss to the ena... [click for details & full pictures]
[details]

Reconditioned Model A
Reconditioned single piston Model A aquarium pump in azure blue.
Some minor cosmetic loss to th... [click for details & full pictures]
[details]

Model A Aquarium Pump
Single piston twin outlet model A aquarium pump.
Good runner in excellent condition.
Serie... [click for details & full pictures]
[details]

Model A Technical / Laboratory Pump
Black Model A technical pump.
A good runner, with both vacuum and air components.
Some min... [click for details & full pictures]
[details]

Super Junior Hy Flo Aquarium Pump
Single piston Junior Hy Flo pump in excellent condition.
Lovely runner.
Series IV piston.
[details]

Model A Aquarium Pump
Single piston dual outlet model A aquarium pump.
In good condition - very minor cosmetic wear,... [click for details & full pictures]
[details]

Single Outlet Junior Aquarium Pump
Single outlet "Super Junior" aquarium pump. Excellent working order with some minor cosmetic wear to... [click for details & full pictures]
[details]

Single Outlet Junior Aquarium Pump
Single outlet "Super Junior" aquarium pump. Very good working order with minor cosmetic wear to the ... [click for details & full pictures]
[details]

Junior Hy Flo Aquarium Pump
Junior Hy Flo in very good working order.
Very minor comsmetic wear - a nice example of an old... [click for details & full pictures]
[details]

Junior Hy Flo Aquarium Pump
Junior Hy Flo in good working order.
Very minor comsmetic wear to the piston casing.
Seri... [click for details & full pictures]
[details]

Junior Aquarium Pump
Junior Hy Flo in good working order.
Good runner - some to the pump shell paintwork.
Seri... [click for details & full pictures]
[details]

Junior Aquarium Pump
Junior Hy Flo in good working order. The pump is dirty and there is some minor cosmetic wear to the ... [click for details & full pictures]
[details]

Model A Aquarium Pump
Early model A in fair cosmetic condition - would benefit from a clean.
There is significant los... [click for details & full pictures]
[details]



- site last updated : Thursday, April 9, 2026 -
- all content and images protected by copyright - ©mmxix

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