Over a dozen different tests are routinely done in the water garden industry in order to ensure the best possible water quality. With tests measuring everything from Alkalinity to Salinity it can be a bit overwhelming to know which tests are needed most.
Fortunately, most water quality experts agree on a handful of tests that every industry professional and pond owner should perform.
AMMONIA – Ammonia is formed when fish waste and other organic debris (leaves, grass, dead fish, or frogs, etc) begin to decompose. This decomposition releases toxic Ammonia into the pond water. A test reading of Zero Ammonia is best but not always possible.
NITRITE – Nitrifying bacteria work on the Ammonia and break it down to Nitrite. Nitrite is also highly toxic to your pond fish and the ideal reading should again be Zero.
NITRATE – Eventually Nitrite is broken down further into Nitrate, which is less toxic to your pond fish although still bad enough in higher concentrations. Ideal reading would be zero. NOTE: Many industry experts suggest testing for both Nitrite and Nitrate in your pond but others believe testing for Nitrite is sufficient.
Norm Meck, former president and 20-year member of the San Diego Koi club, feels that testing for Nitrite is vital due to its high toxicity and danger to the fish. Nitrate, Norm indicates, is far less toxic to pond fish and is also reduced when the pond is treated for Nitrite.
pH – Testing the pH of your pond is critical according to many experts. The ideal pH reading in your pond is debatable by many but is often considered to be 7.0 – 7.5 although pH will vary throughout the day.
According to Freddie Combas, owner of Florida Water Gardens and veteran pond builder, pH will be lowest in the morning and highest in the evening. Someone who tests their pond early morning for pH and again in the evening may see a huge variance in readings. It is important to find an average reading and not be alarmed by a wide swing in the readings during the day.
KH – Carbonate Hardness = Total Alkalinity which is different than pH. Carbonate Hardness is the ability of the pond water to stabilize the pH in the system. According to Dave Jones, owner of The Pond Professional in Woodstock GA, KH should be at least 100 PPM. Ideal KH readings are between 100-200 PPM.
PHOSPHATES – Phosphates are usually introduced into a pond thru fish waste and are a nutrient that algae require to flourish. Algae, like other plants, require many nutrients to grow so the presence of Phosphates alone does not ensure an algae problem is imminent. A reading of Zero PPM is ideal although many ponds can have much higher concentrations with no algae issues present.