4 Good Reasons To Know Your Garden Pond Water Volume
Why You need To Know Your pond volume ... reason 1.
In terms of comparative size a garden fish pond; even a large fish pond will generally have a large percentage of Koi, goldfish and other pond fish in comparison with the volume of pond water. A natural lake or reservoir will have a small percentage of fish in comparison with the overall volume of water.
A natural water system can only cope with a certain fish stocking density, mainly due to limited food sources and biological capacity. The majority of lakes will contain a few large fish and many smaller fish. The large fish have managed to grow to the size that they have by eating the smaller fish, struggling to survive for the available food sources. In natural lake systems it is pretty rare to find large populations of both large and small fish, unless the lake has been artificially stocked at some stage. You will naturally see a fair split of sizes.
For this reason the levels of ammonia excreted into the water by the fish inhabitants will be miniscule in comparison with the volume of water. This combined with the surface area available for nitrifying bacteria to colonize will mean that ammonia problems are extremely like to occur.
However in a backyard fish pond there is nearly always too many fish for the size of the pond and there is a constant battle to control the build up of ammonia, before it reaches toxic levels. That is why a garden pond biofilter is essential. To correctly specify the right pond filter you will need to know your pond volume. It is the volume of pond water together with the fish load that determines the pond size required and the amount of pond filter media required, so that you create a good bio filtration system.
Click here to use my pond volume calculator ...
Use the following information as a general rule of thumb; you can always add more but not less pond filter media.
How much biomedia to treat a 300 US gallons (250 UK gallon) pond ...
Plastic tubes 1 inch diameter and 1 inch high (hollow): 10 to 12 US gallons (8 to 10 UK gallon).
Plastic balls 1 inch diameter: 14 to 18 US gallons (12 to 15 UK gallon).
Lava rock: 2 US gallon (3 UK gallon).
Open cell foam: 6 US gallons (5 UK gallon).
Alfagrog sintered ceramic: 1/2 gallon.
Multiply the US gallon by 3.7854 to get liters or multiply by 4.5 to convert UK gallons to liters.
Pond filter media is where beneficial nitrifying bacteria colonize. The larger the surface area the better; a larger surface area equates a larger colony (biomass). It is these bacteria that ensure the pond water is kept pure and free from ammonia. It stands to reason that the larger the surface area of the pond biomedia the more efficient your pond filter will be.
Why You need To Know Your pond volume ... Reason 2.
Pond volume is also required to specify the size of the UV sterilizer or UV clarifier needed to prevent your pond water from becoming green with suspended algae.
For a fish pond of around 250 gallons in full sun and highly stocked a 4 watt UV will be adequate. A 4 watt UV light will also be adequate for a larger 700 gallon pond with a few fish. The Ultraviolet system must of course be fitted with a quartz tube, to ensure peak efficiency. For a 1200 gallon garden pond, with an average fish stocking density you will need an 8 watt ultraviolet clarifier.
When choosing the UV wattage required, base your choice on the following: lots of sun, lots of fish and high pond water temperature will require a more powerful UV. Do not worry too much if your UV is under powered because you can always add another one in line to your system. Follow the general rule of pond keeping! If in doubt always go bigger.
Why You need To Know Your pond volume ... Reason 3.
If you ever need to add a chemical pond treatment to your garden pond then you must know your pond volume, to avoid over dosing. All pond water additives work on the principle of x amount of ounces per gallon of pond water. There is no room for guess work here; not if you want to keep your fish, nitrifying bacteria and aquatic plants free from harm.
Why You need To Know Your pond volume ... Reason 4.
A fourth reason you might need to know the pond volume is to be able to specify your pond pump. Click here to learn about how to choose the right pond pump ...
TIP! If you are building a new fish pond or water garden and have a water meter then why not take advantage and record the volume of water used to fill the pond.
Click here to use my pond volume calculator ...
