Essential Pond Water Testing For New Pond Builds | Water Tests For Backyard Ponds
You Need To Know Your Pond Volume
You need to know the approximate volume of water in your pond before you are able to determine the number of fish your pond can hold, the amount of water that equates to say a 15% water change and before you are able to use feeding products and pond-maintenance products properly.
For simple shaped ponds the following formulas can be used to determine the actual pond volume. For more complex pond shapes check out my pond calculators ...
Square & Rectangular Shapes |
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Round Shaped Ponds |
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Converting between Gallons and Liters |
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Fish Stocking Density
For successful pond keeping, follow this general rule: for every 24 square inches (155 cm2) of pond surface area, you can stock your pond with 1 inch (2.5 cm) in length of fish. Too many fish in an established or new pond can result in poor water quality and low oxygen levels. Fish require a continuous supply of oxygen to survive ... If you are still unsure then check out my Fish Loading Calculator ...
Why Is A Biological Pond Filter So Important?
Toxic ammonia is continually released into your pond environment from aquatic pond life in the form of urine and solid waste as well as by decaying vegetation, including leaves, plants and algae.
A biofilter is a critically important part of any healthy pond environment. It in essence serves two purposes:
- It removes solid waste matter and leaves from the pond
- It breaks down toxic ammonia and nitrites before they have a chance to poison all forms of aquatic pond life. The actual breaking down of ammonia into nitrite and then into nitrate is performed by 2 species of beneficial bacteria known an Nitrosomonas and Nitrobacter. The end result is nitrate which acts as a food source for aquatic plants. The whole process is known as the Nitrogen cycle or Nitrification process.
When introducing fish to your garden pond it is imperative that you add no more than 2 fish a week. This allows your biofilter to adapt to the increase in ammonia present in the water. During the first month you must carefully monitor the ammonia and nitrite levels every three days using a suitable Pond Test Kit. If the ammonia and nitrite levels continue to rise then this is an indicator that the pond filter (biofilter) is struggling to cope.
At this stage don't add any more fish for the time being, reduce feeding and change 10% of the pond volume on a daily basis. The addition of Pond Care Ammo Rocks to the filter or on the pond floor will not only add a decorative finish to the pond but will also help to break down the ammonia. The beneficial bacteria mentioned early colonize the rocks.
Aquatic plants are not only beautiful, but are helpful in establishing a balanced pond ecosystem. Submerged plants produce oxygen during the day, and the attractive blossoms of surface plants, such as water lilies and water hyacinths, help prevent sunlight from penetrating the pond, thus reducing algae growth. Pond plants also remove phosphate and nitrate, each of which helps algae to grow. Aquatic Plant Stimulants will promote the growth and flowering of all plants without causing algae blooms.
Water Tests For Backyard Ponds - Why Test Pond Water PH?
Healthy fish ponds are a perfect balance of water chemistry. There are many different factors that affect the quality of the water. In terms of fish ponds the pH is commonly talked about! A pond will be either neutral (pH of 7), acidic (pH less than 7) or alkaline (pH greater than 7)
Factors such as acid rain, minerals leaching from soil, rotting vegetation and aquatic life waste matter all have an effect upon the pH of the pond. In general an acceptable pH range is between 6.8 to 7.8 for the majority of aquatic plants and pond life. Extreme pH levels either below or above this range should be treated quickly.
Factors Causing Low pH In Garden Ponds
As the aquatic community within your pond grows you will notice that the pH becomes acidic i.e. below a pH of 7. This is normal as long as it isn't allowed to dip below 6.8, as this causes stress related problems within many fish species, particularly Koi.
Increased carbon dioxide levels, overstocking of fish, inadequate oxygenation, poor surface agitation, decomposing plants and fish waste can all lead to acidic pond water. Use Pond Care Pond Zyme Plus and regular maintenance to eliminate this low pH factor and stabilize the pH.
Water Tests For Backyard Ponds - Why Test Pond Water For Ammonia?
The answer is simple! Ammonia is the #1 killer of aquatic life. This toxic chemical in high enough concentrations poisons the fish! Ever wondered why a goldfish living in a goldfish bowl doesn't live very long? It is systematically poisoned by the ammonia excreted into its home through urine, waste matter and decaying fish food.
A healthy pond where the biological pond filter is working correctly will not have an ammonia reading. All new ponds have a bedding in period whilst colonies of Nitrosomonas and Nitrobacter beneficial bacteria start to colonize. As mentioned earlier they convert ammonia into nitrate. These bacteria consume vast amounts of oxygen as part of this process. It is always a good idea to add additional oxygen in the form of a Fountain or Pond Aerator.
In newly established ponds, without an adequately functioning biofilter (biological filter) you will often find an ammonia reading of 10 parts per million (ppm) or more. This drops as the biofilter beds in and the colonies of bacteria have built up.
As a general rule an ammonia reading of more than 0.25 ppm is an indicator of one or more of the following problems: Overfeeding, overstocking or too much decaying plant life. The increased ammonia level is not necessarily an indicator of the elevated nitrite level. The nitrite level should be tested separately on a regular basis.
How To Reduce Ammonia Levels
As stated previously a new pond filter will take between 2 to 4 weeks to establish itself with a big enough colony of nitrifying bacteria to successfully breakdown ammonia, as it appears. Don't forget that during the initial month you must not add more than 2 fish per week. After both ammonia and nitrite levels drop to nil, more pond fish and aquatic life can be added.
If ammonia is still present after a month then: reduce feeding for one week, remove debris from the pond floor, ensure there is adequate oxygen and surface agitation. If the ammonia reading is greater than 0.50 ppm then change 25% of the pond water every 2 days until the pH reaches 0.25 ppm or less.
Water Tests For Backyard Ponds - Why Test Pond Water For Nitrite?
Again the answer is simple. Nitrite, like ammonia is poisonous to aquatic life. Nitrite is produced as a result of the breakdown of ammonia by the Nitrosomonas bacteria. Whilst not as toxic as ammonia it is nevertheless potentially lethal. Ammonia and nitrite build up quickly in new ponds, especially if there are too many fish, lots of decaying vegetation, excess uneaten fish food and plenty of birds using the pond as a toilet.
As the biological filter nitrifying bacteria colonies increase in size there will be a reduction in the nitrite reading; down to nil when the filter is working optimally. The end result of this bacterial action (the Nitrogen cycle) is nitrate, a source of plant food. Unfortunately however algae is a microscopic form of plant life that also grows rapidly if there is too much nitrate in the water. You will know if you have because the pond will start to turn green.
One way to combat the growth of algae is to utilize Aquatic Plants, who consume the nitrate. Established ponds containing a mixture of pond plants normally have a nitrate level that is less than 140 ppm.
Heavily stocked fish ponds will often have a nitrate reading of 500 ppm nitrate.
Whilst excess nitrate levels will not harm your plant life or pond life it will encourage Algae Bloom. Excess nitrate in ponds is often due to one of the following: overfeeding, overstocking of fish, the addition of too much plant fertilizer and too much rotting vegetation within the pond.
