So when I store my glass carboys I always add about a tablespoon of potassium metabisulphite (PM) in them so nothing will grow/spawn/evolve...... If I put a jar of water and PM in the keezer will this stop mold from growing?
mold is caused by moisture forming and anywhere it sits too long it can grow mold, to prevent moisture in the keezer look here https://www.brewersfriend.com/2010/12/12/moldy-wet-keezer-solution/
Best way to keep mold at bay is by using a desiccant or dehumidifier to reduce moisture and cleaning periodically with a good disinfectant.
You can use silica based cat litter as a desiccant. Then just bake in the oven at the lowest setting to remove the moisture and reuse it. Some examples: https://www.amazon.com/Silica-Gel-Beads/s?k=Silica+Gel+Beads https://www.amazon.com/silica-cat-litter/s?k=silica+cat+litter If i remember correctly Damp Rid uses salt and is only good for one use.
