Which Pipe Fittings & Pipe Type To Use In Garden Fish Ponds

The subject of fittings is confusing and sizes vary depending upon where you live

Why Are Fittings Needed?

In almost any pond you have at least 2 components that need connecting and in some cases more than 3 items of equipment. Most connections start with the pump.

There is a vast variety of pumps for ponds and many these days come with fittings that make life a lot easier. I would always recommend such a pump and the best are probably from these suppliers and all 3 have a very broad international distribution system so you can find them in most countries ...

• Hozelock Cascade fountain or Titan waterfall pumps

• Oase make a wide variety of pumps for fountains, waterfalls, filters and specialized applications

• Fish Mate (Animate) also make a good range of pond filter and waterfall pumps

 More often than not the pipe from the pump needs to change direction and the important thing to remember here is to use a fitting with a smooth bend as you can see in this image to the left. By using smooth bend curves you conserve pumping power. Every pumps loses a bit of flow for every fitting included in the line and the more abrupt the change then the more flow is lost ... this is due to what is called pressure drop.

 If you need to split flow into 2 directions avoid "T" pieces as shown to the left. Based upon what was said in the previous paragraph you'll see that one of the directional changes of the fitting is at 90 degrees. This kind of split creates relatively high pressure drop that translates into lower flow. You'll see from the picture that there are many sizes of pipe fittings and the golden rule is always to choose the widest diameter fitting you can ... once again the reason is to lower pressure drop and therefore minimize the amount of flow that will be lost. A "Y" piece is a much better way to split flow into 2 directions as shown in the next image

 When you use a "Y" piece to split flow then this minimizes friction losses or pressure drop in the fitting. Note the inlet side (white) is of a wider diameter than the outlet and that the 2 outlets have what are called "stepped" fittings shown in red. The idea of the stepped fitting is to make it easier to attach the same fitting to different pipe diameters. Whenever you use any type of stepped fitting attach to the largest diameter pipe you can ... and the CUT OFF the smaller steps so that they do not impede water flow through the pipe and fitting. Some "Y" fittings have valves built into them so that you can control the flows ... maybe you want more in one particular direction than another. If you look closely at the image you will see 2 small in-line valves shown in black. You can even sue to shut the flow off down one of the "Y" legs.

Which is best pipe to use?

Algae will grow on the inside of pipes and therefore it is best to reduce this growth by using opaque plastic pipe that does not allow algae to grow so quickly for the reason sunlight cannot penetrate the pipe.

In this picture you'll see how this perfectly transparent pipe at one stage became lined with algae and this reduces flow possible through the pip

Very often you'll want to bend the pipe and is the second reason transparent pipe is normally not the best choice. Ribbed flexible pipe is by far the best and is perfect for pond keepers... when you bend this kind of pipe it does not kink and act as a restriction to water flow. Most transparent plastic pipes kink very easily and the impact is a lower water flow to your waterfall or fountain.

Take a look at the picture here again ... the pipe comes out from between quite large rocks and it would be easy for these rocks to compress the pipe and therefore reduce flow.

All pipe whichever type you use should be the shortest possible length and the widest possible diameter consistent with the rest of your equipment and the fittings you use. By optimizing these 2 choice your pump will perform at its best.

 When you attach pipe you'll often use what we call Jubilee Clips ... if you do use these then try to use stainless steel clips ... otherwise they have a habit of corroding and being impossible to undo some years down the track