RO is reverse osmosis. It is a way of purifying water of particulate AND dissolved impurities. A fish tank filter or the like will get mostly particulate matter and relatively little of the rest except what the carbon can latch on to.

If you use tap water, be prepared to wipe down immediately after you pull the barrel from the tank. Even so, drips or runs or beads of water have to be eliminated quickly before they dry. A paper towel with denatured alcohol will do it.

Brent

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BrentD, (Professor - just for Stan)
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