Plastic Tank Colors

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The natural color of most plastic storage tank resins is a translucent, milky white.  That works very well in most cases because you can see the level of the stored liquid through the sidewall of the tank. 

There are times when you may be better off by having a plastic storage tank of a different color.  This may be true if the liquid you are storing will be degraded by Ultra Violet light from the sun.  Another color may be beneficial for branding purposes, to communicate that the liquid is hazardous or just to prolong the life of the plastic storage tank.

Water tanks are most often colored black or forest green.  Any color will work so long as the tank is opaque and blocks out the UV rays from sunlight.  Water tanks that have translucent walls will have algae growth that is not desirable.

Bleach (Sodium Hypochlorite) storage tanks are best if they are an opaque white.  Bleach will degrade if stored in a translucent tank that allows the UV rays to come through.  Bleach will also degrade under higher heat that comes from using black or dark colored plastic tanks for storage.  A white, opaque tank is the recommendation of the Bleach Council.  In years past, most bleach was stored in black plastic storage tanks and some companies have not kept up with the change in tank color recommendations.  There is significant difference in the temperature of a stored liquid in a white tank versus a black tank on a hot summer day.

Black tanks are good options when the chemical does not degrade from higher heat.  The black walls limit the UV rays that affect the inner part of the plastic tank wall.  The Ultraviolet rays have a negative impact on polyethylene so opaque walls will prolong the life of the tank.  One down side of opaque tanks is the need for level gauges of some type to let you keep track of the fill level of the liquid in the tank.  If the tank is in a building and already sheilded from sunlight, a normal translucent tank is less expensive and just as effective.