No change, an alternative
Both K.O. and Odorlos work with the naturally occurring bacteria in nature (waste) to break it down, and both utilize the same aerobic principles to prevent odor--the ONLY two products on the market that do work with nature instead of against it. For the bacteria in K.O. to function aerobically, they need a sufficient supply of oxygen from an external source (the tank vent) to keep the tank aerobic, and therefore odor free. The active ingredient in Odorlos is nitrates, which extract oxygen from the waste itself...so it doesn't need as much oxygen from external souces as K.O...so it often works in tanks that don't get enough oxygen to allow K.O. to work. So they're equally good products, each with it's own upside and downside: Because the bacteria in K.O. multiply, they're "self-renewing"--rarely any need to add more between pumpouts unless the boat has sat unused long enough for the little buggers to die--and they keep up with the rate of bacteria multiplication in waste, even in the hottest weather... but K.O. needs more oxygen than is available in some tanks.Odorlos needs less oxygen, but the nitrates exhaust themselves, requiring additional doses as more waste is added to the tank, and in hotter weather. So which one I recommend depends on how well the tank is vented. Sometimes I think that Odorlos has a better chance of eliminating odor than K.O. If neither works, nothing will till some surgery is done to improve the ventilation in the tank.