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Gardening, Ponds & Aquatics > Koi Supplies > Koi Pond Water Chemistry
Koi Pond Water Chemistry
Water quality is vitally important when keeping Japanese koi. Improved water quality is essential for the prevention of sickness and disease. If the basics of water chemistry and maturation can be understood then the health, vitality and appearance of your fish will be the envy of all your friends, family and neighbours.
The ponds and lakes of Japan where these fish are raised are fed each spring by natural melt water from the mountainous regions. Natural water parameters are detailed in the following sections:
pH parameters
The ideal pH level for your koi should be between 6.8 and 7.5. Anywhere outside these parameters and your fish will suffer adverse affects. Serious swings in pH can even result in death. For example, a very low acidic pH of 5.5 and below can lead to irreparable damage to the gills and gill function.
Water Hardness
Your pH level is governed by your water hardness (the amount of dissolved salts present in your water). Rainwater contains no dissolved salts and is prone to dramatic fluctuations in pH. River or spring water contains dissolved salts particularly calcium and magnesium to a lesser (soft water) or greater (hard water) degree. Both calcium and magnesium react with carbon dioxide in your water, this continuous reaction forms carbonates which ?buffer? your water and maintain a stable pH. The general hardness (GH) of your water is governed by the amount of carbonate minerals (KH) and non carbonate minerals (NKH) present in your water.
GH = KH + NKH
General hardness (GH) is measured in degrees.
- 0-4 = very soft water, generally acidic and of low pH, not suitable for koi
- 4-8 = soft but pH well buffered, suitable for koi
- 8-12 = moderately hard, ideal for koi
- 12-18 = very hard, not suitable for koi
There are many ways to achieve the correct pH and GH of your pond, the use of calcareous media (high in calcium) in your filtration i.e. oyster shells or limestone rock. Also available are a variety of chemical or salt products which when administered to your pond will help to maintain stable and suitable parameters.
Trace Elements
Trace elements are a reserve in your pond that must be replaced. In Japan trace elements are dissolved in to the water table through water passing through volcanic rock and clay. Trace elements are important to koi as they encourage the development of pigment in the epidermis improving skin and colouration. Iodine is one of the important trace elements which aid the thyroid gland which controls metabolism. Trace elements can be introduced using products like Nishi clay or even standard marine trace elements.
Check back soon for advice about:
- Carbon Dioxine
- Nitrogen Cycle
- Ammonia & Ammonium
- Nitrite
- Nitrate
- Oxygen
- Pathogens
To speak to an expert about Koi, please call 0161 304 704
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