White Knight is 24%.peroxide.
Sally’s is 40 Volume.
Sally’s is about half as strong as White Knight.
Divide Volume by 3.3 to get percentage.
40 / 3.3 =12% (~Stain Magic). (Proxy is about 7% peroxide).
Multiply peroxide percentage by 3.3 to get Volume.
12% x 3.3 = 40 Volume (Sally’s)
2 cups of 24% diluted with 2 cups of water (distilled or Di is best) in a quart trigger bottle and you have an inexpensive version of Sally’s 40 Volume.
One gallon of White Knight costs $30 delivered to your door.
The amount of Sally’s needed to be equivalent to one gallon of White Knight would be 2 gallons or 8 quarts.
At $5/quart, 2 gallons of Sally’s = $40, plus a whole bunch of trips to the beauty supplier, pretending to be a girl, LOL.
Get White Knight.
How long peroxide lasts depends a lot on the type of water you add as well as temperature inside the van.
As for the types of water, Di or Deionized water is best. We use Di water to blend peroxide formulations because there are little to no impurities in Di water for the unstable oxygen radical to react with. Sealed containers of peroxide and Di water will go weeks before you see any swelling of the jug.
Distilled or RO water is also good.
Distilled is pretty easy to come by and you will get several days in the van before its potency drops off significantly.
Outside temperature and temps in the van is another biggie.
All these peroxide formulations go flat faster in hot work vans.
Whereas you might get a week out of potent peroxide sitting in the van during winter, you may only get 1-2 days in summer.
Still, peroxide is so useful as a spotter and prespray additive, it’s worth it to keep a quart trigger on the van at all times.
Never keep your gallon jugs of peroxide on the van.
Keep them inside, out of the heat, preferably in the refrigerator; away from the kids of course.
A longer life peroxide is the powdered version, like CTI’s OSR.
The most common are powdered peroxides are called percarbonate and perborate.
My products CT BOOSTER and JOSR have a lot of peroxide (13% peroxide), along with an activator that keeps it active even when the water cool off.