http://www.water-treatment.org.uk/water_treatment_chemicals.html
Water Treatment Chemicals
This page is intended to provide you with a description of some common water treatment
chemicals, along with links to commercial suppliers.
Algicide
An algicide is a chemical which when added to water kills algae and blue-green algae. Some
examples of common algicides include copper sulphate, chelated copper-based products,
benzalkonium chloride and simazine. Whilst effective in reduction of algae the use of
algicides to control algal blooms is not recommended for environmental reasons and the
chemical should only be used in emergancy cases. Like all chemicals this should not be
considered a long term solution to algal problems.
All copper-based algicides will damage and in most cases kill algal cells. This reaction leads
to the release of algal toxins in to the water, these toxins can pass more easily through the
water treatment filters than the intact algal cells. If algicides are used in potable water
supply reservoirs the water should not be used until the toxins and odours degrade which
could take several months.
It is a lot more difficult to detect algal toxins than whole algal cells. So once algal cells are
killed, the only way to determine whether algal toxins are still present in the water is through
toxin testing. The toxins produced by blue-green algae are generally very stable compounds
that are resistant to chemical breakdown and may remain in natural waters for several
months.
Some risks associated with using copper-based algicides include:
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The accumulation of copper in the sediments;
The growth of species of blue-green algae that are resistant to the algicide may
cause greater water quality problems;
The mass release of toxins from the algal cells;
Buy algicides online
Chlorine
Chlorine is, essentially, bleach although it is not said to be harmful in small quantities it has
been linked to cancer as a known carcinogen (cancer-causing agents) when combined with
naturally occuring acids. Chlorine is such a big subject area I can't hope to cover it all hear
but you can find more information on how to use Chlorine and may other delightful facts on
the sites below:
Chlorine Online
Chlorine.org.uk
Clarifiers
Primary Clarifiers help slow the speed of the wastewater to allow the solids to settle out side
of the wastewater. A secondary clarifier can be used to settle out microorganisms from the
activated sludge process.
Clarifiers typically have rotating arms, which help to remove scum from the surface of the
water. The sludge or biosolids are usually collected at the bottom of the clarifier and then
sent to a digester for further treatment.
For further information you can see the following pages:
Information about a inclined plate clarifier
Information about parallel plate clarifier Information on circular mechanical clarifier
Filter Cleanser
Is an acid-based granular formulation that cleans and unclogs sand and cartridge filters of
grease, oils and sludge.
You can buy it at the following sites:
Swimthings.com
Kusuri.co.uk
Dry or Muriatic Acid
Dry or muriatic acid can be used to decrease the pH of your water and should be used
according to the manufacturars instructions otherwise you could end up with water at a
danerously acidic pH level.
Soda Ash or Sodium bicarbonate
Soda ash or sodium bicarbonate can be used to increase the pH of your water and should be
used according to the manufacturars instructions otherwise you could end up with water at a
danerously high pH level.