Chlorine and chloramines. A more stable form of chlorine compound

The water companies, to keep the water we consume free from pests and diseases, add these chemicals to the water supplies in compound form. Unfortunately these chemicals and the free chlorine gas that they release are highly toxic, to Koi carp in particular.

Much of the gas can be dispelled from the water by spraying it into the pond at pressure. Any further chlorine will be expelled by further oxygenation. This may take anything from 7-10days during which we may say the water 'ages'.

This process can be speeded up with the use of a proprietary chemical 'Pool Conditioner'. Not only will this dissipate the chlorine but any other halogens. It will also help the heavy metals, common in our water supplies, to harmlessly drop out. The fish are further helped by a special protective colloid that mimics the natural secretions of the fish and so helps protect them from their environment and reduce the effects of stress. This makes it doubly useful if you have to move the fish for any reason, and it is an essential additive for whenever you have to top up or do a partial water change.

(A halogen is any one of the five elements, fluorine, chlorine, bromine, iodine and astatine that exist in a free state as diatomic molecules.)

There is a school of thought that a little bit of knowledge in this department can be a bad thing. That if you start off with all the right ingredients and keep within the prescribed parameters then a natural biological balance will evolve eventually. The less you tamper and test, pry and manipulate, the more the environmental system will be able to look after itself.

That is until the pond's ambition to become 'a mere boggy place' is beginning to be realised.