# powdered brightener



## Stretch67 (Oct 7, 2013)

Tried a couple jugs of Penofin brightener in solid form. Premixed with water n stirred real well in a 5er b4 putting in pump sprayer. The stuff doesnt dissolve real well; at end of day I was left with a couple inches of granules in bottom of pump sprayer... anyway to get the solids broke down better so they go through?


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## straight_lines (Oct 17, 2007)

Hot water and a mixer on a drill.


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## Hines Painting (Jun 22, 2013)

Definitely hot water.

And are you trying to mix too much in?


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## Stretch67 (Oct 7, 2013)

Hines Painting said:


> Definitely hot water.
> 
> And are you trying to mix too much in?


Ill try hot.

Not sure. Eyeballing two cups per gallon of water. I made pretty close to 8 gallons with 1 jug of powder


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## PressurePros (May 6, 2007)

Warm water is fine. Too hot and the powder will crystallize. Most of that crap sold in paint stores has filler so the most you can dissolve is usually 8 oz (dry weight) per gallon. If using pure oxalic powder you can get 30% more to dissolve into solution. You have to stir it for a couple minutes, let it sit then stir again.


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## CRS (Apr 13, 2013)

Oxalic acid is not infinitely soluable in water. Sounds like that particular company need to work on their formulation for their brighter. We have been using a blend of Oxalic Acid and citrus acid. Much easier to mix and avoids residue an windows. Dry powders - from chemical supplier....very inexpensive. Most as powerful as phosphoric acid but way safer.


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