Aw you`re welcome Dr. Rayeye, mmm control patina - I have a few carbons and acidic foods and red meats can react fast sometimes.
Personally I would not want to control the patina, if it`s thick enough it can brush off most food types and you get a knife with character like an old pair of jeans or an old leather wallet etc.
I would just use it normally and build the patina up naturally.
Chefs generally don`t leave reactive carbons damp for too long so they wipe the blade as required.
I would not scrub the blade with an abrasive unless it went rusty and would just rinse in warm water only avoiding over use of detergents, bleaches and surfactants and dry thoroughly after every use.
None of my yellow, white or blue carbons are very reactive thank goodness but I have 2 pairs of scissors that go brown within minutes of air exposure and they need powdered citric acid, salt and bicarb to strip them first then camellia oil on straight away.
I`m trying to build up patina which takes time.
If I had knives that bad I`d throw them away or give them away because they`re such a PITA.
If you`re going to store it or use it in a humid environment I would just put a light coating of food safe mineral oil or even better camellia oil on the blade.
In my experience camellia works better than 3 in 1 oil, WD40 spray or mineral oil.
The Japanese have been using it on carbon blades for Centuries.
After a while it just becomes second nature and you hardly notice the slight extra maintenance compared to stainless.