Pond Volume Explained

Where do we start?....
Pond size! First... we need to establish the size of the pond to calculate its gallonage. Unless we get this right everything else will be a waste of time. The size of the pond governs the amount of water to be filtered.

How do we calculate this?
The diagrams below show a simple way to assess the volume of an irregular shape by breaking it down into smaller sub units.

In this example the pond has been divided in two main sections A and B. Measure each section in feet. All figures should be rounded UP to the nearest whole foot. For filtration purposes you would be better to over estimate the volume. (This only applies to filtration calculations and NOT for medication. It is GOOD to over filter but BAD to over medicate). The volume of each section is calculated using length x width x depth. This gives us an answer in cubic feet. Each cubic foot holds 6¼ gallons of water. The volumes of the two sections (A & B) should then be added together to give the total cubic capacity. This is multiplied by 6.25 to give the total volume in gallons.

REMEMBER
Do not under estimate the size of your pond!

1. Pre-filter Used to extend pump maintenance intervals buy preventing, debris, newts, frogs etc. being sucked into the pump
2. Submersible pump. Sucks water from the pond and pumps it through the UV to the filter.
3. lexible Pipe. Routes the water from the pump to the UV.
4. UV Algae Master. For the control of green water algae.
5. Magnetic venturi. Oxygenates the water and helps to prevent limescale and blanket weed.
6. Pump fed filter For mechanical and biological filtration. To colonise bacteria (for biological filtration), removes waste and improves water quality.
7. Filter return. Return flow back to pond. Could be via a waterfall or other water feature.
8. Water level of pond.
9. Vacuum pipework. Necessary on installations when larger surface pumps are fitted. Soft and low grade pipe could collapse due to the strong vacuum produced by these pumps.
10. Surface pump. Normally installed reasonably close to the pond but not submersed or in any position where flooding is possible. These pumps usually pump more water at a greater pressure and tend to be more efficient.
11. Sump bottom drain installed at the lowest part of the pond where fish waste etc. would normally fall and accumulate

Pump Fed Vortex Filter System
A vortex is used to settle out waste products and heavier solids. Water is injected along one side to induce a whirlpool effect called a vortex. This encourages the heavier solids to sink and the cleaner water to rise to the outlet. This will reduce the workload of the filters by removing most of the heavy solids and fish waste also reducing filter maintenance.

Pump fed filters are installed above the level of the pond. Water is pumped up to the filter and allowed to fall back to the pond

Filter shown without media for clarity

To work correctly, the first vortex in the system must be fed via the inlet port (shown left). Vortex units may be joined together in various configurations to provide greater pre-filtration or to form part of larger multi-bay filter systems. The example below left shows a dual vortex system to provide extra settlement while the example below right shows a vortex followed by extra vortex units used as filter bays

Gravity Fed Filter System with Vortex chamber and Cartridge Filter
The installation shown below is a very popular configuration and gives extremely good results. The diagram clearly shows the correct order in which the filtration system should be assembled . Fish waste and other solid particles fall to the bottom of the pond where they are drawn into the bottom drain (1) and on via the large diameter pipe (2) to the Vortex (3). Gravity systems should be fed by large diameter pipes as they offer less resistance to the water flow (as no pressure is available other than gravity). 3” and 4” pipes are the most popular. The whirlpool action of the Vortex causes the heavier particles to fall to the bottom where they can be drained off. This decrease of heavy waste to the main filter (4) increases its performance and reduces the maintenance. The water is then sucked through the vacuum pipe (5) by the surface pump (6) and pumped through the Cartridge filter (7) and then the UV (Ultra Violet Algae Master) (8). The water exits the UV still under pressure from the pump and is pushed through the magnetic venturi (10) to the pond. This action causes air to be sucked in (via the magnetic venturi) and mixed with the water, thereby increasing oxygen levels in the pond and filtration system. To simplify the drawing and maintain clarity we have omitted several items from the diagram including: drain valves, drainage pipework and filter media. (9) is a Yamitsu switch box.

Gravity filters are installed at the same level as the pond. The water is pumped back to the pond.

Larger diameter pipe is used on Gravity inlet

Alternative Filter Installations

Expanding your Filtration System
The diagram below shows an easy and economic way to use a single pump to operate a dual filtration system. The pump sucks water from the Gravity fed filter (mounted at pond level) which fills from the pond.It then pumps water through the UV and up to the Pump fed filter (positioned above the pond’s water level). The water then falls back to the pond from the filter outlet completing the cycle.. This type of filtration expansion is often used to good effect when an existing Gravity fed system is no longer adequate for the pond it is supporting. An additional pump fed filter can be added in the return pipe work to the pond This type of expansion requires no additional pump or associated costs. We recommend the Yamitt pump (shown below) as it offeres high performace and low running costs.

With thanks to Yamitsu for the use of the information above

Yamitsu filters can be purchased from Koi Logic at the best price and with the best advice.