Which Pond Equipment is right for your Application?

A brief discussion of pond pumps, filters and there applications, benefits and draw backs:

Pond pumps:

Pumps are available in many sizes to suite different purposes. It is important to choose the correct pond or water feature pump for your specific application. Most pumps are mains operated with solar pumps becoming more popular for smaller features although they are generally underpowered. The name of a pump often includes a number which usually refers to its maximum output in litres per hour, the box will tell you its maximum flow rate and also its maximum head, often depicted on a graph. Head refers to the distance the pump can push water vertically for instance up to a waterfall or water feature. It is important to remember that maximum head and maximum flow are both independent of one another and are achieved at ground height straight from the pump with no restrictions or resistance caused by pipes, fitting and other equipment. With this in mind we must first determine what we want from our pump, how many litres per hour and at how much head. There are calculations to determine how much resistance our pipes and fittings will cause; these can be added to the head which makes it easier to determine our total head. Once we know what we want from our pump we can decide which pump will work best for us.

Pumps for Filtration and water features

volume vs pressure

integrated, separate spout, pre-filters,

Pump – In Pond/Submerged

wildlife protectors, bypasses, split use/strainers etc

Pump – External/Dry

External pond and water feature pumps are more commonly used in commercial and larger scale water features. An external pump can be located in a pump room or housing where it is easier to access for maintenance and servicing, it must however have sufficient air circulation to keep it cool and must also be kept dry.

 Pond Filters:

Pond filters comes in many designs and perform a variety of functions often in combination. There are three main categories of filtration: biological, chemical and physical. Biological covers the use of naturally occurring flora and/or fauna. Chemical filtration includes any man made or modified substances. Physical filtration includes any mechanical aids which trap or remove waste.

Filter – Pressurised Canister

 

Filter – Gravity fed box

 

Filter – Pressurised sand/bead filter

Natural Filtration

Vortex

Settling Chamber

Venturi etc

 

Pond Pipe and Connectors:

Why is choice important? When choosing a pipe we must first think about its application, what do we need to achieve? What pressure will it be running at? how many bends do we need to go round and how far are we moving the water?

Flexible PVC pipe

A ribbed PVC pipe available in several sizes (bore) often black but available in several shades. A single rib runs around the pipe in a spiral giving reinforcement whilst allowing for flexibility. A fairly cost effective choice. quality varies greatly with price and manufacturer. Great for most garden pond applications as it is easy to cut and connect, fairly robust and quite easy to bend round corners. It allows us to remove submerged pumps from the water without having to disconnect them first.

Rigid PVC pipe

A solid construction PVC pipe available in several sizes (bore) and pressure ratings. This pipe is more common in the more complex systems used for larger Koi pond or commercial water feature set ups. It requires pipes and connectors to be primed and glued to make good connections. It allows for very sharp corners allowing it to follow walls and solid obstacles closely. It can be rated to take a greater pressure than flexi pipe and is usually available in white and black. The wide variety of fittings available allow for a large choice of connections including screw threads. can be painted to camouflage.

Copper pipe

Often associated with traditional domestic plumbing this comes in a variety of sizes and is connected via fittings and heat welding. not commonly in use for water features as Rigid PVC is easier to use but is does have a place in some water features where the pipe will be visible and a metallic finish is required. Other metal finishes can be found.

 

Pond/Under water Lighting:

Lighting your pond or water feature can increase your enjoyment into the dark hours. It adds an evening feature to the garden and looks great. Use them as stand alone lighting or in conjunction with a garden lighting set up.

Pond Lights – Basic set up and components

A basic pond light set up would have a circuit breaker for safety then a transformer which reduces the voltage down to an acceptable level for use in and around water. This is wired up to lights one to the next until the final light is reached where it would terminate. A sensor known as a day/night switch can be fitted before the lights which will allow programming or timing for lights triggered manually or by dusk.

Halogen vs LED pond lighting

Until recently underwater lighting has only been available with Halogen bulbs. They are available in a selection of colours and wattage. These produce heat as well as light which can cause waterproofing  problems as it swells and shrinks the light unit when in use breaking seals and causing condensation. The more recent LED varieties are superior in that they are lower wattage using less electricity, they don’t produce heat and are now available in warm white as well as several colours.

Lights can be set up to vary in colour and produce disco like displays or to simply give a classy highlight to the pond, streams and waterfall or water feature. They can be automated, manually switched or remote controlled.

There are several makes of plug and play or click and go lighting available which allow for easy and quick assembly although for heavier duty jobs a bespoke set up is preferred.

Light units themselves come in a variety of plastic and metal finishes with price tags to match appearance and quality.

 

Pond Algae control equipment

Ultra Violet Clarifiers and sterilisers (UVC)

 

Ionising units

 

Ultrasonic units

 

Aeration and Oxygenation

Most pond and water feature applications use aeration systems with oxygenation reserved predominantly for aquaculture applications. Oxygen levels can be raised by adding air artificially via an aeration system or naturally via falls, movement and increasing surface area.

Ponds with a high stocking density can benefit from aeration, especially in times of high demand or low dissolved oxygen: like post feeding, hot days and early morning.

We also use aeration systems to move the water. If you have a dead space within a pond or water feature where waste settles and doesn’t get drawn into the filter pumps. Aeration lifts the water causing movement and thus circulation.

The equipment used in a basic aeration system starts with an air pump. These can be outdoor rated or are housed in a shelter. They use a flexible membrane to draw air in and then push it out through the outlets. It is normal to use a very small bore tube and connectors to carry the air from the pump to the desired location. It is here that we add our diffusers. These come in many shapes, sizes and materials, basically they are a porous material which breaks up the air into smaller bubbles. The better the material the smaller the bubbles, the smaller the bubbles the greater the volume of oxygen diffused into the water. Also the greater the resistance and therefore the larger the pump required. In most applications an airstone will work well with ceramic diffusers for more commercial applications.

Aeration can be added via a venturi system, these use the movement of water within a pipe to draw or suck in air through a small hole or pipe. This is a power free method which allows the air to diffuse as the water moves through the pipes. It is not widely used these days.

Lots of people prefer to add a water feature to create movement and aeration. These include fountains, jets and waterfalls. Waterfalls are a great way to increase oxygenation as they greatly increase exposure to air, diffuse via drops and the surface movement exposes more water to air, they can be run from the filter as a return to the pond. Fountains and jets look good, create a visual feature and increase diffusion directly and again through surface agitation.