Aquaponics - Water testing

Its extremely important to make sure your water quality is within a desirable range. Aquaponics is remarkably stable and robust, but, for the first few weeks of setting up a new system it can require a little extra care. The best way to avoid any problems is to test your water every day until your system is mature and in balance or "cycled". (pictured here taking 30 days or so)

An aquaponics system is said to be cycled when it can process approximately 1 ppm of ammonia into nitrites and then process those nitrites into nitrates within 24 hours.

A decent freshwater test kit will enable you to get accurate test results for pH, ammonia, nitrites, and nitrates. It will set you back around 50 Australian dollars. They are widely available online or any good aquarium shop should sell them.

If you try aquaponics without water testing you will lose fish unless you are very lucky.

Add ammonia until you see a reading of 2ppm, then wait until your tests show ammonia is 0. Then add more and continue until your system can process 1ppm of ammonia and nitrites in 24 hours. Once you see readings of 0 ammonia and 0 nitrites you are cycled and can add fish.

Plants can be added on the day you first build your system but there wont be much for them to live on for a few days. My house water supply is rainwater and has some nitrates in it from normal environmental nutrient. Even normal tap water will have some nitrates in it so there will actually be something for small seedlings to live on.

Be careful to wash the soil from any store bought seedlings you transplant as they may have any number of additives that may be toxic to an aquaponics system. Growing directly in the grow beds from seeds is safest (and often quicker!)

Conduct water testing every day until you are cycled and then test every week or so or if ever anything strange occurs. Plants yellowing or dying can be a sign of something being wrong with your water chemistry and you might need to intervene in the early stages of your aquaponics system setup. More on correcting water problems later.

Always keep a record of your tests so that you can see emerging trends before they become an issue.