Aquaponics involves the dynamic interaction of fish, plants, bacteria, and their aqueous environment. The fish and plants are dependent on the balance of dissolved nutrients and quality of the water, as they generate and utilize metabolic products from each other. It is this unique balance that leads to healthy animals and a productive crop. Because of the symbiotic uptake and release of nutrients from fish to plants, periodic monitoring of your aquaponic system water is essential.
There is a multitude of commercially available water testing systems ranging from water test strips and kits to electronic meters. Both strips and kits can be obtained at local aquarium shops, while multiparameter aquaculture kits and electronic meters must be mail ordered. The choice(s) of which method to use can be particularly daunting, especially for those who are just starting in aquaponics. That is why I have searches linked to so you can get an idea of what's up. It will be a little bit farther down the page
Water in your aquaponic system is the life of the system. It is the medium that moves the oxygen, macro- and micro-nutrients and from plants to fish. The water is the most important thing to understand. Because if you screw it up everything dies.
There are five key water quality parameters - dissolved oxygen (DO), pH, temperature, total nitrogen, and water alkalinity. Each parameter has an impact on all three organisms in the unit (fish, plants and bacteria), and understanding the effects of each parameter is crucial.
Don't let that scare ya. The knowledge of water quality and water chemistry needed in your aquaponic system may seem daunting, but the management is relatively simple, with the help of some testing kits. Water testing is absolutely essential for the task of keeping good water quality in your system.
Oxygen is essential for the three life forms (organisms) to co-exist in harmony in your aquaponic system. Plants, fish and nitrifying bacteria all need oxygen to live. The DO (dissolved oxygen) level describes the amount of molecular oxygen within the water, and it is measured in milligrams per liter. It is the water quality parameter that has the most immediate and drastic effect on your aquaponics.
Your fish may die within hours if your DO drops to low in your fish tanks (they suffocate). Ensuring adequate DO levels is crucial to aquaponics. Although monitoring DO levels is very important, it can be challenging because accurate DO measuring devices can be very expensive or difficult to find.
So in a small system, you have to rely on frequent monitoring of fish behavior and plant growth. Just make sure that the water and air pumps are constantly circulating and aerating the water.
Copy and paste these into the search box below and get 8 examples.
Accutest strips, Tetra kit, Hack kit,
Or click the searches and go to a different tab and see how many options that you have.
Accutest strips
- Tetra® kit - Hach® Kit -
Interactive change keywords and see
A basic knowledge of ph is helpful in managing your aquaponic system (it needs to be monitored daily). The pH of your solution is a measure of how acidic or basic the solution is. The pH scale ranges from 1 to 14. A pH of 7 is neutral; anything below is acidic, anything above is basic. The term pH is defined as the number of hydrogen ions (H+) in a solution; the more hydrogen ions, the more acidic.
Two important aspects of the pH scale
• The pH scale is negative; a pH of 7 has fewer hydrogen ions than a pH of 6.
• The pH scale is logarithmic; a pH of 7 has 10 times fewer hydrogen ions than a pH of 6, 100 times fewer than a pH of 5, and 1000 times fewer than a pH of 4.
For example, if the pH is tested at 7 and then later recorded at 8, the water now has ten times less freely associated H+ ions because the scale is negative and logarithmic. Now if you get a reading of 9, the problem would be 100 times worse, and therefore hypercritical, instead of just being two times worse.
The Importance of pH
The pH of your water will impact every aspect of your aquaponic system. For the plants the pH controls access to micro- and macro-nutrients. A pH of 6.0-6.5 all nutrients are available, but outside this it become a little more difficult for them to eat.
Nitrifying bacteria has problems when the pH gets below 6, and the bacteria's ability to convert ammonia into nitrate reduces in acidic or low pH conditions.
Fish have specific tolerance ranges for pH as well, but most fish used in aquaponics have a pH tolerance range of 6.0–8.5. However, the pH affects the toxicity of ammonia to fish, with higher pH leading to higher toxicity.
Water temperature affects everything in your aquaponic system. A good range to shot for is 64.4-86 °F (18–30 °C). Temperature has an effect on the DO as well as the toxicity (ionization) of ammonia. The higher temperatures have less DO and more unionized ammonia which is toxic. Higher temperatures can restrict the uptake of calcium in your plants. Your fish and plants should be chosen to match the ambient temperature for the systems' location, and changing the temperature of your systems water can be expensive. Warm-water fish (tilapia, common carp and catfish) and nitrifying bacteria thrive in higher water temperatures 71.6-84.2 °F (22-29 °C)
The fourth crucial water quality parameter is nitrogen. Nitrogen is required by everything that lives and is part of all proteins. Nitrogen enters your aquaponic system originally through the fish feed and is usually labeled as crude protein and measured in percentages. Some of the protein is used by the fish for growth, the remainder is released as waste by the fish. The waste is mostly in the form of ammonia (NH3) and is released through the gills and as urine. Solid waste is also released, some of which is converted into ammonia by microbial activity. This ammonia is then nitrified by bacteria, and converted into nitrite (NO2) and nitrated (NO3). Nitrogenous waste is poisonous to fish at certain concentrations, ammonia and nitrite are approximately 100 times more poisonous than nitrate.
Nitrogen compounds are toxic to your fish they are nutritious for your plants and are the basic component of plant fertilizers. All three forms of nitrogen (NH3, NO2- and NO3-) can be used by plants, but nitrate (the most toxic to fish) is by far the most accessible. In a fully functioning aquaponic unit with adequate bio-filtration, ammonia and nitrite levels should be close to zero, or at most 0.25–1.0 mg/liter. The bacteria present in the bio-filter should be converting almost all the ammonia and nitrite into nitrate before any accumulation can occur.
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Water hardness is the last water quality parameter. The final water quality parameter is water hardness. There are two major types of hardness: general hardness (GH), and carbonate hardness (KH). General hardness is a measure of positive ions in the water. Carbonate hardness, also known as alkalinity, is a measure of the buffering capacity of water. The first type of hardness does not have a major impact on the aquaponic process, but KH has a unique relationship with pH that deserves further explanation.
General Hardness
General hardness is basically the amount of calcium (Ca²+), magnesium (Mg²+) and to a lesser extent iron (Fe+) ions in your system's water. It is measured in parts per million (equivalent to milligrams per liter). High GH concentrations are found in water sources such as limestone-based aquifers and/or river beds, as limestone is essentially composed of calcium carbonate (CaCO3).
Both Ca²+ and Mg²+ ions are essential to plant nutrients, and they are taken up by plants as the water flows through the hydroponic components. Hard water can be a useful source of micro-nutrients for aquaponics and has no health effects on the organisms. In fact, the presence of calcium in the water can prevent fish from losing other salts and lead to a healthier stock.
Carbonate Hardness or Alkalinity
Carbonate hardness is the total amount of carbonates (CO32-) and bicarbonates (HCO3-) dissolved in water. It is also measured in milligrams of CaCO3 per liter. In general, water is considered to have high KH at levels of 121–180 mg/liter. Water sourced from limestone bedrock wells/aquifers will normally have a high carbonate hardness of about 150–180 mg/ liter.
Carbonate hardness in water has an impact on the pH level. Simply put, KH acts as a buffer (or a resistance) to the lowering of pH. Carbonate and bicarbonate present in the water will bind to the H+ ions released by any acid, thus removing these free H+ ions from the water. Therefore, the pH will stay constant even as new H+ ions from the acid are added to the water.
This KH buffering is important because rapid changes in pH are stressful to the entire aquaponic ecosystem. The nitrification process generates nitric acid (HNO3), which is dissociated in water in its two components, hydrogen ions (H+) and nitrate (NO3-), with the latter used as a source of nutrients for plants. However, with adequate KH the water does not actually become more acidic.
If no carbonates and bicarbonates were present in the water, the pH would quickly drop in the aquaponic unit. The higher the concentration of KH in the water, the longer it will act as a buffer for pH to keep the system stable against the acidification caused by the nitrification process.
There is a multitude of commercially available water testing systems ranging from water test strips and kits to electronic meters. Both strips and kits can be obtained at local aquarium shops, while multiparameter aquaculture kits and electronic meters must be mail ordered. The choice(s) of which method to use can be particularly daunting, especially for those who are just starting in aquaponics. That is why I have searches linked to so you can get an idea of what's up. It will be a little bit farther down the page
Water in your aquaponic system is the life of the system. It is the medium that moves the oxygen, macro- and micro-nutrients and from plants to fish. The water is the most important thing to understand. Because if you screw it up everything dies.
Key Water Quality Parameters
There are five key water quality parameters - dissolved oxygen (DO), pH, temperature, total nitrogen, and water alkalinity. Each parameter has an impact on all three organisms in the unit (fish, plants and bacteria), and understanding the effects of each parameter is crucial.Don't let that scare ya. The knowledge of water quality and water chemistry needed in your aquaponic system may seem daunting, but the management is relatively simple, with the help of some testing kits. Water testing is absolutely essential for the task of keeping good water quality in your system.
Oxygen
Oxygen is essential for the three life forms (organisms) to co-exist in harmony in your aquaponic system. Plants, fish and nitrifying bacteria all need oxygen to live. The DO (dissolved oxygen) level describes the amount of molecular oxygen within the water, and it is measured in milligrams per liter. It is the water quality parameter that has the most immediate and drastic effect on your aquaponics.
Your fish may die within hours if your DO drops to low in your fish tanks (they suffocate). Ensuring adequate DO levels is crucial to aquaponics. Although monitoring DO levels is very important, it can be challenging because accurate DO measuring devices can be very expensive or difficult to find.
So in a small system, you have to rely on frequent monitoring of fish behavior and plant growth. Just make sure that the water and air pumps are constantly circulating and aerating the water.
Water Quality Testers and Kits
Copy and paste these into the search box below and get 8 examples.
Accutest strips, Tetra kit, Hack kit,
Or click the searches and go to a different tab and see how many options that you have.
Accutest strips
- Tetra® kit - Hach® Kit - Interactive change keywords and see
pH
A basic knowledge of ph is helpful in managing your aquaponic system (it needs to be monitored daily). The pH of your solution is a measure of how acidic or basic the solution is. The pH scale ranges from 1 to 14. A pH of 7 is neutral; anything below is acidic, anything above is basic. The term pH is defined as the number of hydrogen ions (H+) in a solution; the more hydrogen ions, the more acidic.
Two important aspects of the pH scale
• The pH scale is negative; a pH of 7 has fewer hydrogen ions than a pH of 6.
• The pH scale is logarithmic; a pH of 7 has 10 times fewer hydrogen ions than a pH of 6, 100 times fewer than a pH of 5, and 1000 times fewer than a pH of 4.
For example, if the pH is tested at 7 and then later recorded at 8, the water now has ten times less freely associated H+ ions because the scale is negative and logarithmic. Now if you get a reading of 9, the problem would be 100 times worse, and therefore hypercritical, instead of just being two times worse.
The Importance of pH
The pH of your water will impact every aspect of your aquaponic system. For the plants the pH controls access to micro- and macro-nutrients. A pH of 6.0-6.5 all nutrients are available, but outside this it become a little more difficult for them to eat.
Nitrifying bacteria has problems when the pH gets below 6, and the bacteria's ability to convert ammonia into nitrate reduces in acidic or low pH conditions.
Fish have specific tolerance ranges for pH as well, but most fish used in aquaponics have a pH tolerance range of 6.0–8.5. However, the pH affects the toxicity of ammonia to fish, with higher pH leading to higher toxicity.
Temperature
Water temperature affects everything in your aquaponic system. A good range to shot for is 64.4-86 °F (18–30 °C). Temperature has an effect on the DO as well as the toxicity (ionization) of ammonia. The higher temperatures have less DO and more unionized ammonia which is toxic. Higher temperatures can restrict the uptake of calcium in your plants. Your fish and plants should be chosen to match the ambient temperature for the systems' location, and changing the temperature of your systems water can be expensive. Warm-water fish (tilapia, common carp and catfish) and nitrifying bacteria thrive in higher water temperatures 71.6-84.2 °F (22-29 °C)Total Nitrogen: ammonia, nitrate and nitrite
The fourth crucial water quality parameter is nitrogen. Nitrogen is required by everything that lives and is part of all proteins. Nitrogen enters your aquaponic system originally through the fish feed and is usually labeled as crude protein and measured in percentages. Some of the protein is used by the fish for growth, the remainder is released as waste by the fish. The waste is mostly in the form of ammonia (NH3) and is released through the gills and as urine. Solid waste is also released, some of which is converted into ammonia by microbial activity. This ammonia is then nitrified by bacteria, and converted into nitrite (NO2) and nitrated (NO3). Nitrogenous waste is poisonous to fish at certain concentrations, ammonia and nitrite are approximately 100 times more poisonous than nitrate.
Nitrogen compounds are toxic to your fish they are nutritious for your plants and are the basic component of plant fertilizers. All three forms of nitrogen (NH3, NO2- and NO3-) can be used by plants, but nitrate (the most toxic to fish) is by far the most accessible. In a fully functioning aquaponic unit with adequate bio-filtration, ammonia and nitrite levels should be close to zero, or at most 0.25–1.0 mg/liter. The bacteria present in the bio-filter should be converting almost all the ammonia and nitrite into nitrate before any accumulation can occur.
continue reading below Amazon Search
Interactive change keywords and see
Water Hardness
Water hardness is the last water quality parameter. The final water quality parameter is water hardness. There are two major types of hardness: general hardness (GH), and carbonate hardness (KH). General hardness is a measure of positive ions in the water. Carbonate hardness, also known as alkalinity, is a measure of the buffering capacity of water. The first type of hardness does not have a major impact on the aquaponic process, but KH has a unique relationship with pH that deserves further explanation.
General Hardness
General hardness is basically the amount of calcium (Ca²+), magnesium (Mg²+) and to a lesser extent iron (Fe+) ions in your system's water. It is measured in parts per million (equivalent to milligrams per liter). High GH concentrations are found in water sources such as limestone-based aquifers and/or river beds, as limestone is essentially composed of calcium carbonate (CaCO3).
Both Ca²+ and Mg²+ ions are essential to plant nutrients, and they are taken up by plants as the water flows through the hydroponic components. Hard water can be a useful source of micro-nutrients for aquaponics and has no health effects on the organisms. In fact, the presence of calcium in the water can prevent fish from losing other salts and lead to a healthier stock.
Carbonate Hardness or Alkalinity
Carbonate hardness is the total amount of carbonates (CO32-) and bicarbonates (HCO3-) dissolved in water. It is also measured in milligrams of CaCO3 per liter. In general, water is considered to have high KH at levels of 121–180 mg/liter. Water sourced from limestone bedrock wells/aquifers will normally have a high carbonate hardness of about 150–180 mg/ liter.
Carbonate hardness in water has an impact on the pH level. Simply put, KH acts as a buffer (or a resistance) to the lowering of pH. Carbonate and bicarbonate present in the water will bind to the H+ ions released by any acid, thus removing these free H+ ions from the water. Therefore, the pH will stay constant even as new H+ ions from the acid are added to the water.
This KH buffering is important because rapid changes in pH are stressful to the entire aquaponic ecosystem. The nitrification process generates nitric acid (HNO3), which is dissociated in water in its two components, hydrogen ions (H+) and nitrate (NO3-), with the latter used as a source of nutrients for plants. However, with adequate KH the water does not actually become more acidic.
If no carbonates and bicarbonates were present in the water, the pH would quickly drop in the aquaponic unit. The higher the concentration of KH in the water, the longer it will act as a buffer for pH to keep the system stable against the acidification caused by the nitrification process.
Aquaponics System Water Testing Part 1 - pH Overview
Published on Sep 17, 2014
Join us in the Grow Lab as Sylvia breaks down water testing, starting this week with pH testing. The API test kit is a great one to have and we've got them at The Aquaponic Source Store.
We also invite you to join our AP Community of gardeners at http://community.theaquaponicsource.com/
Thank you for stopping by and reading my post "Aquaponics Water Quality" Hope that it didn't give you an information over-load (almost did me). There is a lot of information out there but, all you really have to do is monitor your water. The video will lead you to a series of video (follow to youtube) that should help you learn how to test your water.
Keep Smiling
reuben
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