I am a groomer and I use E-Z GROOM enzymatic whitener.
You need to call them and order some for your dogs who need whitening.
I use their products about 98% of the time in my shop, unless I have a pet there who needs a medicated shampoo (from a vets prescription) or some other specific special product.
They are a great company, and theirs is one of the few whiteners that really works.
Go to ezgroom.com and you can get ordering info from there.
Tell them Sue sent you! lol
Sue & Cricket