The Un-Filters 401

Chapter 6

How Ionizers Work

An ion is simply an atom or group of atoms that’s electrically charged. Ions get their charge by losing or gaining electrons, through friction, chemical reaction or electrolysis, the term for applying an electrical current to the atoms. Electrons are negatively charged; if the ion gains an extra (negative) electron then it will be a negative ion (anion). If it loses an electron it will be positive (cation). For swimming pools, fountains and pond-free features, the typical ionizer has a pair of copper (or copper/silver/zinc) electrodes set in the plumbing line coming from the pump so that water will flow between them. When a small amount of DC current is applied to the electrodes, suspended in a conductive medium (water), atoms of copper are stripped of two electrons and these copper ions are immediately attracted to oppositely charged atoms with extra electrons on the opposite electrode. If (AND ONLY IF) a strong current of water is flowing between the electrodes, these Cu++ ions are swept away from the opposite pole, down the pipe and into the water feature. Circuitry inside the controller changes the polarity regularly, so that the loss of copper alternates between the two electrodes, prolonging their life. Once in suspension in the water, they will be attracted to atoms with an opposite, negative charge. Guess what charge algae cells carry? That’s right, negative, so the copper ions bond to algae cells, breaching the cell wall and killing the cell. Other ions bind to enzymes and proteins, keeping the cell from growing or reproducing. In the proper concentration, copper ions can control floating, rooted, surface and suspended algae.