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post #6 of Old 10-16-2002
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Fresh water tank slime

This is a phenomenom of ''chemical equilibrium'' meaning if the carbon is ''hungry'' for molecules/iond and those molecules/ions are present in the system (even if not flowing) these molecules (in this case chlorine ions) will migrate and affix to the surface of the carbon. What happens is that the carbon will remove the Chlorine from the system and leave NO chlorine in the system to ''stun'' any remaining bacteria, spores, etc.
sooooooo even if the water isnt flowing, the ions ARE flowing and in this case TO the carbon filter. The only way to prevent this ionic migration is to shut the valves on the carbon filter each time you use it.

Its not a big problem in a household system as enough chlorine will constantly migrate in from the system supply even if the supply is non flowing. ..... but on closed system such as a boat, there no replentishment possible except for continually dumping more Chlorine into the tank.

I''m deeply involved in water systems and especially filtration. Why I DO NOT have (ANY) filters installed on my boat''s water system are: 1. Trapped bacteria, molds, etc. on a filter eventually dies and the accumulated (now highly concentrated!) cell debris (endotoxins) can release from the filter and reenter the system ... gives you FEVER, etc. A filter concentrates the bacteria. 2. Many bacteria THRIVE on carbon as they use it as part of their nutrient source (consider that most of YOUR food is also carbon based... and what your cells eat is essentialy: glucose).... long term, bacteria will even ''eat'' the carbon from steel pipes, etc. , etc. (.... thats probablly how metal ores were formed in the earth.... bacteria ate away the carbon).
The data sources are limitless ... just do a websearch for "USP water", "Water for Injection" (WFI water), "validation of water systems" etc. etc. From these searches you will find zillions of sources and documentation (including US-FDA regulations) of purity water systems.

Just be aware that the stagnant water system on a boat is VERY close to a bacteria, etc. incubator - non-moving, dark, warm, .... so in my mind why would I want to also supply food (carbon) to enhance cell growth !!!!!

A good ''starter'' reference would be "Pure Water Handbook", Osmonics Corporation. 2ed. 1997 (paperback) ph: 612-933-2277 ($10). But the handbook DOESNT cover "stagnant" systems.
However, current ''bottled'' water specs. would probably apply as the "bottle" on my boat is 120 gallons.

hope this helps.
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