Although the silver metal membrane is 99.97% pure silver, the formation of extraneous compounds is possible over time. For example, silver can become tarnished, especially when the environment contains certain emissions as described below. To minimize contamination of the membrane, leave it in sealed packs. Silver compounds may form on the surface which are primarily cosmetic imperfections and do not affect the pore structure or membrane filtration performance. Examples of colored compounds that can form on the surface of the silver metal membrane are:

• Ag₂S (black)
• Agl (yellow)
• Ag₃PO₄ (yellow)
• Ag₂CrO₄ (dark red)
• AgCl (dark brown)
• Ag₂O (dark brown)
• AgBr (light yellow)

The most common compounds that form on the silver metal membrane are Ag2S and AgCl. AgCl is a photosensitive salt that can be removed by flushing the membrane with an ammonia solution. Typically, just a brief soak or dip in the ammonia solution will dissolve AgCl. Ag2S is a very stable compound and is very difficult to remove from the membrane without altering the structure. A flush with methyl or ethyl alcohol can be used to remove some of the other compounds.

These compounds should not be confused with the natural grayish white appearance of the silver metal membrane surface. This appearance is due to the microporous structure of the media which reflects light in a manner different than polished silver. The slight difference in color between the two sides of the membrane is due to the manufacturing process and is most noticeable on 3 and 5 micron pores sizes.