Guide to Pond Pipe Fittings, Connectors, & Valves

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Most pond equipment will be connected through some form of pipework, including your main pump and filtration system. Understanding the best type of piping to use, and when to add valves and connectors, will allow you to get better reliability and efficiency from your system in the long run. Below we’ve provided an overview of common pond hose types, connectors, valves, and fittings, as well as explain why each item is useful and how to use them optimally when designing a pond.

Pond Pump Hose Piping – What’s the Best?

Pond Keeping Tip: Make sure you purchase the correct type and size of pipe for your equipment, and always double check piping & valves before gluing solvent-weld connections together.

1) Flexible Pond Hose

Sealproof Flexible PVC Pipe 2 Inch Dia Hose 50 FT Length, Black Tubing, Schedule 40, Premium Quality...
  • 2" ID, 50 FT Length. For use with PVC Schedule 40 type fittings. Use with Listed PVC solvent cements and primers. Flexible for easy handling...
  • Manufactured in the United States from high quality virgin PVC compound. Phthalate Free. Smooth Surface
  • Flex PVC wall and cover for ease of use . Outside diameter tolerance +.020 inch. Rigid PVC spiral resists crushing and impact

Best used for: Small-Medium pond builds with simple pump/filter systems.

Flexible pond hose is the cheapest and most flexible type of pond pipework, and is commonly used in most small-large lightly stocked fish ponds. The hose is generally made from a UV resistant reinforced PVC material, and comes in a range of designs, including clear hose, green clear hose, and ribbed-hose. The major advantage of using flexible pond hose is its ability to shape to whatever design of water garden you have, easily bending around tight corners where an elbow fitting would usually be needed with rigid pipework. As well as this, flexible pond hose can be installed in much longer lengths, with maximum distances being around 100ft (30m), which makes creating longer plumbing frameworks much easier. Common ID sizes of flexible hose range from as small as 0.125″ to as large as 2″, although 1-1.5″ is the most common in garden ponds.

The main disadvantage of flexible pond is that it doesn’t support many valves and accessories that are widely used in the koi hobby, making things like maintenance and cleaning more difficult in larger systems. It can also look less professional in comparison to a rigid pipe framework, with the flexible hose often being difficult to hide due to its length and lack of accessories.

Even with the disadvantages, flexible hose is a simple, cheap, and easy option for most pond owners with simple pump to filter arrangements. For larger ponds, especially those with heavy stocked koi, moving to a rigid pipework set-up may be better in the long term for easier management and more versatility. If you do select flexible hose, we would recommend a ribbed black hose as it stops algae forming in the pipework and does not kink as easily around tight bends.


  • Flexible for tight corners.
  • Allows long lengths.
  • Easy for beginners.


  • Unsightly & hard to hide.
  • Dose not allow valves/connectors accessories.

2) Rigid Pond Piping

letsFix 3/4" PVC Pipe, DIY PVC Projects for the Home, Garden, Greenhouse, Farm and Workshop, Sch. 40...
  • ✅Furniture Grade PVC Pipe - Ideal choice for your DIY PVC structures & projects. PVC Greenhouse, PVC Sheds, PVC Shelves, PVC Tent...
  • ✅UV Resistant - Infused with UV inhibitors to allow the pipe to be used in the sun. Will not crack, change color or degrade over time like...
  • ✅Pure White - No mark, No logo on it and glossy surface finish gives a clean, professional appearance that makes your projects look...

Best used for: Large koi ponds, gravity-fed systems, or multi-filter set-ups.

Although less common for smaller garden pond designs, rigid pipework is very popular within the koi hobby, providing more options when it comes to maintenance. As the name implies, rigid pipework isn’t flexible like regular hose, so needs to be arranged carefully with a variety of joints, elbows, valves, and connectors. This type of pipework is more durable in comparison with soft PVC hose, and works great for koi ponds, breeders tanks, and gravity fed installations. If you have any experience with regular house-hold plumbing, you’re already ahead of the game and can quickly take advantage of a rigid pond arrangement. There are many types of pipework and bore sizes available, with solvent-weld pipes being particularly durable and efficient, and ID sizes ranging from 0.5″ to over 3″ inner diameter. When selecting pipework, you should avoid plastic pipework with push-fit connectors that are sealed with rubber “O” rings where possible, as these do not handle well under higher pressures.

The major advantage of this pipework is you can create a professional and tight framework and can include a range of valves and accessories to make maintenance easier. For example, installing ball valves helps you isolate certain equipment for easy repairs and upgrades. Likewise, installing a gate valve before your main filter box can help with purging pipes, or connected to a sump tank for quick water drainage. Since there are many more components to larger fish ponds, being able to quickly isolate parts of the system and regulate water flow comes in very handy when you encounter problems.

The main disadvantage is it’s not as easy as flexible hose, and is likely overkill for smaller ponds with simple equipment arrangements. Even though it’s cheaper to purchase the pipework, the added valves and accessories can quickly inflate costs, and these are where the main advantages of this pipework originate. Definitely recommended for larger fish ponds or more complex equipment arrangements, but flexible hose is still a great choice for smaller pond setups or lightly stocked ponds.


  • Allows for higher pressures.
  • Supports valves, connectors, & fittings.
  • Looks professional.


  • Harder to set-up as beginner.
  • Extra connectors are essential (since non-flexible).

Pond Pipework Valves – What’s Useful?

Pond Keeping Tip: Use plenty of valves! Fit as many valves as you can when using rigid pipework, as this will help you isolate faults, upgrade equipment, drain water, and maintain water for priming.

1) Pond Check Valve

Jandy 7305 180-Degree, 2-Inch to 2-1/2-Inch Check Valve
  • For straight through flow
  • Clear lid with red seal for easy inspection
  • Unique swing/spring design for both return and intake water

Best used for: Priming external pond pumps and to stop water flow after pump shut down.

A simple valve with multiple uses, a check valve works by opening with fluid flow in one direction and closing if water flow is reversed or stopped. The most common types operate with “swing” disc or a rubber diaphragm, with a swing valve working on a simple hinge and a rubber valve flexing under different fluid pressures. For use in pond systems, swing check valves are much more common (pictured) as they’re designed for larger pressures and work with larger bore sized pipework. There is no need for manual control as check valves open and close automatically with changes in water pressure, making them very useful in certain pond arrangements.

The best use for check valves is to assist with the priming of external pond pumps and maintaining water in leaf baskets (priming pots). Since external pumps, even self-priming models, require water for operation, check valves are useful for keeping a constant supply in the pipework and priming pot in-between uses. For example, a common arrangement would be a check valve on the intake of an external pump’s priming pot, so that when the pump is turned off (and water pressure drops), the valve will close but water will be retained in the priming pots main chamber. This prevents water draining from the pump so priming is easier and the pump doesn’t become “air bound” and damaged when it’s started again.

2) Pond Ball Valve 

HYDROSEAL Kaplan PVC 1 1/2" True Union Ball Valve with Full Port, ASTM F1970, EPDM O-Rings and...
  • APPLICATION - Commercial plumbing, aquariums, reef tank, irrigation, swimming pools, water parks and OEM applications
  • CONSTRUCTION - SOCKET (GLUE ON ONLY), 2 EPDM O-rings and 2 PTFE seats for long-lasting, superior performance
  • FULL PORT - Full flow fluid handling characteristics for long-lasting, superior performance in the field.

Best used for: Priming external pond pumps and to regulate flow manually.

A wonderfully useful valve which regulates flow using an internal ball which is operated manually using a handle. These valves are popular in plumbing due to their ease of use and wide range of applications, allowing you to section off parts of the system for upgrades, repairs, or flushing. The valve works with a metal ball with a hollow center that pivots 90-degrees when the handle is turned. The valve is open when the hollow center is in-line with the water flow, and closed when the ball is pivoted 90-degrees using the handle. A double union design means you have a threaded union fitting on both sides, making it much easier to disconnect from pipework. We’d recommend a double union ball valve for pond installs, especially around equipment, or you’ll be cutting into pipework if you want to perform any upgrades!

Handy in many parts of a pond system, especially before and after an external pond pump or filter box, allowing you to manage the equipment without cutting into pipes. They’re also great for stopping flow when equipment needs to be cleaned, or for priming external pumps below the water line by keeping a certain amount of water in the pipework when the pump is turned off.

3) Pond Autofill Valve (Float Valve)

Little Giant AFV-GH Auto Fill Valve / Pump Up Valve, for Ponds, Fountains, Water Features, Aquariums...
  • APPLICATIONS: Works with most skimmers and other pond/fountain equipment or reservoirs to allow water to automatically fill the vault, basin...
  • ADAPTERS INCLUDED: 1/2-inch MNPT valve comes with a 1/2-inch pipe adapter, 1/2-inch barbed adapter for 1/2-inch tubing and a 3/4-inch garden...
  • ADJUSTABLE: will maintain the water level approximately 1.25 inches below the horizontal centerline on the auto-fill mounting hole; adjust...

Best used for: Maintaining water levels in the pond or within skimmer boxes when attached to water source.

An autofill valve, float valve, or “ballcock” valve is an interesting valve which provides a method of maintaining a constant water level in ponds or skimmers. The valve works via a float which sits on the top of the water and opens or closes the valve intake depending on the current level of fluid. A similar type of valve can be found in most toilets around the world, working to drain water when the toilet is flushed, and then slowly filling until the float reaches the ideal level which closes the valve door. The name “ballcock” comes from the fact that many original models used balls as floats, however, in recent times there are a variety of different shapes and sizes.

Their application is very useful for pond keepers in very warm and dry countries where evaporation occurs more rapidly. In most cases, float valves can be purchased to fit directly to a garden hose, making them incredibly easy to install and use. You’d leave the water running and the float would dictate whether the valve allows water into the pond through the mains supply based on the current water level. Another common use would be inside a skimmer box system so you can maintain a more optimal water level for better surface skimming and to prevent the internal pump running dry due to water loss.

4) Pond Gate Valve (Drain Valve)

NDS GVG-1500-S ProGuard Gate Valve, 1-1/2 in, IPS Hub, SCH 80 PVC, Gray Body, Handle, 1-1/2-Inch,...
  • Branch off the main supply line to create a feeder line that supplies water to a low-flow, drip-watering device, or use as a main line in a...
  • Tubing outside diameter (OD) is 0.250 in., internal diameter (ID) is 0.170. in.; connect to main supply line with 1/4 in. micro fitting such...
  • As part of a complete drip irrigation system, the supply tubing transports water to the area to be irrigated; Tubing coil comes...

Best used for: Waste drainage from filter system or sump tank. Simple On/Off design.

Probably the simplest valve you can install in your pond system, but one that is very useful for water purging and waste drainage. Pond slide valves, or gate valves, operate using a basic open/close design where you manually regulate the flow with an attached handle. Particularly well suited for draining waste from filters or for emptying water from a sump tank, but can also used to isolate equipment where a ball valve isn’t suitable. The advantage of these valves is their simple mechanism and cheap purchase price compared to ball valves. However, they need to be glued into the pipework and cannot simply be removed once installed like a union fitted ball valve. We would recommend a ball valve for most situations where you need to regularly work with equipment, although a gate valve is still useful for waste drainage systems which require less “hands on” maintenance.

Pond Hose Fittings – What’s Useful?

Pond Keeping Tip: Even though flexible hose has no valve options, you can still get some control with adaptors such as flow regulators. Clamps should always be used with flexible hose when fitting!

1) Pond Hose Splitter

Laguna Y-Connector with Click-Fit Couplers, 3 at 1-1/2-Inch length
  • Effective way to evenly split water flow
  • Equipped with three 1-1/2-inch click-fit connectors
  • Does not restrict water flow

Best used for: Separating water flow to different pond equipment (i.e., 2 fountains).

Threaded multi-hose adapters or T/Y-pieces are useful for both flexible hose installations and rigid pipework arrangements. Also known as “splitters”, these fittings literally divide the water flow inside your pipework, which can be useful for powering multiple equipment pieces. For example, if you have a pond pump with plenty of head height wiggle room, you can use a splitter to power both a fountain display and a small filter system without the need for two separate circuits. For rigid pipework, they’re even more useful as you can fit a number of control valves to the outlets of each line and easily regulate the flow of water to different parts of the system. Y/T-pieces don’t come multi-threaded so you’d need to make sure the piece matches your pipework ID size. For flexible hose you can purchase multi-threaded adapters (i.e., as pictured), which can be helpful if you have a variety of different hose ID sizes in your circuit.

2) Pond Hose Reducer Adaptor

Laguna Multi Hose Adapter, 1/4 to 1-Inch
  • Measures 1-inch length by 7-1/2-inch height by 4-1/2-inch width
  • It is easy to install and provides a secure connection
  • Designed for both metric or imperial hose sizes

Best used for: Adapting different size hose to different out-take/in-take connections.

For flexible hose only, and similar to the design found in some multi-threaded splitters (as above), allowing you to connect different hose ID sizes together in your system. Simple in design, but incredibly useful if you’re struggling with different types of hose and need something as a connection piece. Although these can be used on their own, we always recommend using clamps to hold the flexible hose in place on both the inlet and outlet. These pieces are designed to bridge a connection, but are not designed for high water pressures often found in pond pipework. Picking up a pair of basic hose clamps to secure your hose in place is the best way to ensure you don’t get major leaks using these adapters.

3) Pond Flow Regulator

Two Little Fishies ATL5445W Ball Valve for Regulating Water Flow, 1/2-Inch
  • Two Little Fishies Ball Valve
  • Barbed Aquatic Ball Valve for regulating water flow
  • Used for devices such as canister filters, pump return lines, protein skimmers, calcium reactors, etc.

Best used for: Reducing water flow to equipment or water features where pressure may be too high.

Although not useful for isolating equipment faults like some pipework valves, flow regulators are a convenient way to regulate the water flow going to pond equipment. They are not designed to stop water flow altogether (hence, “regulator” not “shut off”), but instead work with a simple disc to slow or speed up water flow from your pond pump. This is carried out using a basic handle on top, which moves an internal disc or gate to adjust the flow of fluids.

If you have a pump which is a little too strong for your fountain, waterfall, or filter system, a flow regulator may be the ideal choice to reduce flow and prevent damage. Even though it is always better to size equipment beforehand, adding a flow regulator is a good solution if you already have equipment in place and want more optimal flow from your pond pump.


Chris G
About the author

Chris G

Pond consultant and long-time hobbyist who enjoys writing in his spare time and sharing knowledge with other passionate pond owners. Experienced with pond installation, fish stocking, water quality testing, algae control and the troubleshooting of day-to-day pond related problems.

Read more about Pond Informer.

9 thoughts on “Guide to Pond Pipe Fittings, Connectors, & Valves”

  1. I have just purchased Kockney Koi yamitsu ball valve, it would take king Kong to open and close it .I do not want to fit it in case I break the pipe trying to open it.I do not want to send for a replacement because I could get another one that does not open or close.I want the valve for a waste pipe from a barrel would a slide valve be a better choice, it will be fitted to one and a half inch pipe.

  2. I would like to connect a 2inch flexi pipe to a 2inch solid but can’t find a connector do the job have you any suggestions please.

  3. I have a water feature with a 15mm copper pipe for the water. How can I fix a 25mm flexible pond hose to it. I can’t find any kind of fittings
    To do the job? Thanks

  4. Hi,
    How can I stop water build up in my air pump supply hose, please note, this isn’t back flow from the pond but air condense build up. Can I introduce a water/air separator.

  5. I recently cut out a filter from our pond on an extended rehabilitation project and would like to keep the water running. I believe we have 2″ sealproof hose and I am trying to find a 2″ barbed union/coupler. So far I have not found a coupler on line and wonder if you have a recommendation?


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