pH for KOI Fish

pH is in a range of 0-14.

Sulphuric Acid has very low pH. Caustic soda in solution of water has a very high pH

Nearly everybody knows sulphuric acid is dangerous and that it burns the skin. Well sulphuric acid which is an aqueous solution of sulphur trioxide is extremely acidic (very very low pH and corrosive and dangerous therefore). Sulphuric acid is known as a strong acid. On the other hand vinegar which is a solution of the organic acid Acetic acid is a weak acid and as we all know can be taken in small doses with other fish (and chips)

At the other end of the pH spectrum is the strongly alkaline property with a maximum pH value of 14. Solutions of caustic soda would be considered as strong bases or alkalis.

A weak alkali is sodium bicarbonate in solution. This may be taken for upset stomachs or for baking cakes perhaps. Chemical reactions between strong acids and strong alkalis are extremely vigorous and give off large amounts of heat instantaneously.

Halfway between 0 and 14 is Neutral pH=7

  1. The stronger the acid the lower will be the pH.
  2. The stronger the alkali (or base) the higher will be the pH
  3. Halway between 0 and 14 is pH=7… we tend to think of water as being oh pH = 7 or a neutral pH but this is rarely the case. Water in a pond is either alkaline or acidic. To put this into perspective and to use a real world example consider 2 trout streams in the UK

The one is in the north of Scotland and the water source is essentially rain falling onto stony hills and mountains before running off quickly to form a stream which could quickly turn into a raging torrent. Such a stream would tend to be acidic and would be characterised by low fish populations small in size and low aquatic growth. Fish would be small and stunted in view of poorly fertilised water. Scottish rivers in general are therefore acidic or at best neutral pH=7)

The other stream is in the south of England and is called the River Test. This stream unlike the Scottish one has been formed by rainwater which has first of all sunk into the ground through porous limestone and found its way through these alkaline passages and underground chambers to later find its way out of these chambers to form streams and ultimately rivers. It costs a fortune to fish for River Test trout because of the quality of water and the fact its high pH favours growth of aquatic plants and all life forms that depend upon these plants.

This means a koi pond that is alkaline will support more life forms than one that is acidic.

Almost all lifeforms re-energize as air or water temperatures increase and koi or goldfish are no different. The urge to start life afresh is there for all living creatures and organisms. Some start to spring to life earlier than others after a prologed rest over the winter months in the koi pond.

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