In Part I we covered Components 1 thru 5 of our dream system. We detailed planning the pond, where to locate it, how deep to make it, the shape of the pond and how it affects circulation of the water. We offered helpful tips on measuring and installing the liner, installing the bottom re-circulation drain, the fish-safe skimmer and all valves needed for the system to run properly. We hope our coverage of basic plumbing helped simplify the installation. Our aim is to show you that it is not impossible for the homeowner to tackle this project and do it right! We stopped after Component 5, The Pump.

The basic system was installed in Part I. Most the plumbing was run and the heart of the pond, the pump, was installed. Your system could be operational at this point if you simply ran a water pipe from the pump to the top of your waterfall and plumbed in your induction jets. The water would pump from the bottom and cascade over the waterfall and there would be lots of oohs and ahhs from neighbors and friends — and from you when you first see it running. It would be stunningly beautiful — for about a day or two.

The components remaining to install (the filter and the UV) are considered by some to be optional. We DO NOT consider them optional if the goal is to achieve a healthy, clean and manageable pond. If running short on cash the installation of the filter and the ultraviolet water clarifier unit can be “postponed” and installed later though most prefer to bite the bullet and finish it all while the backyard is in the “construction” mode. If fish are introduced into the pond immediately a biofilter must be in place.

This may seem to be trivial but it sure helps to plan ahead when you are building your pond to make it easy on yourself later. The force of water pressure from a powerful external pump can blow the seal off the head valve of any bead-style filter if you turn the valve to the “CLOSED” position while the pump is running. Once a week or so you will be backwashing the bead filter and will need to change the position of the valve several times during this process. Make it easy on yourself to turn off the power to the pump whenever you change positions on the valve by installing a switch that will turn the power of the pump on and off right next to the bead filter.

A bead filter is one of the most important components for a pond to become healthy and as maintenance-free as possible. Its primary function is to filter out mulm and small debris present in any pond. This makes it a mechanical filter. Without a mechanical filter the pump will continually circulate small debris — all debris small enough to go through the skimmer basket and leaf trap on the pump. Basically, the water stays dirty. The bead filter also provides a home for good bacteria that create the nitrifying cycle responsible for maintaining healthy water for aquatic life. Thus, the bead filter serves a dual purpose, keeping the water clean and healthy.

On the outside the bead filter looks just like a swimming pool filter. The ProBead 65, 120, 210, 360 & 450 models are grey canisters equipped with a head valve that sits on top of the unit that controls the direction of the water flow. On the inside it is quite different. The bead filter is filled with thousands of tiny plastic beads that trap small particles as the water is pumped through the unit. The head valve is set at “FILTER” for normal 24 hours / 7 days a week operation. The bead filter is extremely easy to clean. All one has to do is turn off the power to the pump, change the valve setting to “BACKWASH”, turn the pump back on and let it run for a few minutes. The tiny beads are jostled around, releasing the dirt and debris trapped while the unit was filtering so that they can be flushed out of the system. The valve is set to “RINSE”, let run for a few minutes then back to “FILTER”. This is one tool that our business cannot do without. The sheer labor cost involved with cleaning filter pads on all our systems would drive us out of business.

The bead filter, because it is a compressed unit, can be placed just about anywhere provided the pump is strong enough to push the water to it and through the rest of the system. The minimum gallons per hour pump we recommend to be used with the bead filter is a 4000 gph; otherwise the system may not have enough water pressure to properly backwash the unit. A filter that is not properly cleaned can turn anaerobic. On the other hand, a 2 hp external pump is too strong for the bead filter. The water pressure will literally blow the valve off the top of the filter. In this case, it would be necessary to install a tee and valve after the pump so that only half the water goes through the filter.

The size of the unit will depend on two things; amount of gallons of the pond and fish load. For example: The ProBead 65 is designed for a system of up to 1000 gallons with a “normal” fish load. Our definition of “normal fish load” and yours may not be the same, but for the sake of rating the filter, we take for granted that the pond will not be too overstocked. Still, if you have 1000 gallons you may want to choose the next size up.

Where you decide to place the filter is up to you. It’s best if the unit is sitting level and we recommend that you do not bury it. PVC or flex hose is run from the pump to the bead filter. The opening for the water to go into the unit from the pump is clearly marked “pump”. There are two openings for water to go out of the unit. Many choose to place a discharge hose on the opening marked “waste” to guide the waste water wherever they choose for it to go. Whenever the unit is backwashed the dirty water is expelled from the system through this outlet. The outlet marked “return” is plumbed so that it returns to the pond.

From The Pond Construction Edition -- Part II of What's Up, Doc?, December 2000
© Copyright 2000, The Pond Doc's Water Garden Center. All rights Reserved. Reproduction of this article prohibited without prior consent of The Pond Doc.

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