Currentsea, no criticism intended, but I think you need to spend a little more time reading the labels on the specific products to cut down on any confusion you may have...
1PKO22 and 1PKOGAL (KO - Kills Odor) are exactly the same thing, only in different-sized containers. KO is not a Concentrate - it is used full-strength.
It would (as Kurt mentioned) appear that you are confusing KO with Raritan "Concentrate," ("CON22," also called "RC") which is also sold in a 22 oz. bottle which has a very similar label on it. However, Concentrate is a completely different product, for a completely different application, and the two are NOT compatible with each other - you can't use both of them together.
The reason KO is offered in the gallon size, is that is is quite popular on the large houseboats on the lakes and reservoirs in the central part of the country, and they have very large holding tanks - a 22 oz. bottle of the stuff simply won't cut it in a 200 gallon holding tank.
Factory retail price (BoatFix prices are lower) for the 22 oz bottle is $13.50 ($0.61/oz.) and for the gallon jug it is $45.00 ($0.35/oz.), so the gallon quantity is definitely a better buy. BUT - its shelf life is only 1 year, so don't think you can store it for extended periods of time and it will still work - it won't! More about this below.
KO is strictly a holding tank additive. Nothing more. It is a live bacteria in liquid form, that speeds up the natural biological action inside the holding tank, to reduce, liquify and kill the odor of the contents of the holding tank. It gets into the holding tank by being flushed in through the toilet at the rate of 4 oz. per 25 gallons of tank capacity. The tank must first be pumped out and flushed out with clean water, then the KO is added. If the tank is well-ventilated, it will last until your next pumpout. Then everything must be repeated.
A little more on KO's shelf life -- KO is a live bacteria, and like anything else that is alive, it must be fed in order to survive. In the case of KO, it is fed by what you're pumping into your holding tank. But if you store it sealed-up in its container for extended periods of time without feeding it, it starves to death right there in its container, and it will not work when you put it into the tank. That's the same reason that KO won't work in holding tanks that the boat owners don't send any solids to, they only send urine. Urine, unless you're very ill, is sterile! So it offers no nourishment to KO's bacteria, causing the bacteria to starve to death and die off - and then the holding tank stinks of urine!
Raritan "Concentrate" (RC or CON22) is a toilet deodorant and lubricant only. It comes in concentrated form, and is intended to go into the toilet via the Crown Head, Atlantes or Toilet Water Kit injection systems. It is not for general use with just "any" toilet; it is only for the Raritan toilets that have the deodorant injection systems built into them, or have the injection kits added to them. RC and KO are NOT compatible with one another - each neutralizes the other, so if you use the two products together, your net result will be NOTHING; neither one of them will work.
There are other Raritan products that are also offered in the 22 oz. size: "CP - Cleans Potties," a toilet bowl cleaner. "BC - Bilge Cleaner" for cleaning bilges, and "CU - Cleans Up," a general purpose detergent and cleaner. All of these have similar-looking labels on the container, but they're all different, and are used for totally different applications.
So before purchasing them or using them, be sure to read the labels, so you know exactly what you have there in your hand.
(you're absolutely right!) 