How to Seal Potable Water Tanks


A tank used to store potable water must be sealed correctly. Any contact with materials that could react with the water, such as steel, could impart a flavor that makes the water taste unpleasant. The substance also could make the water a health hazard. You can seal a tank with two-part epoxy paint. Epoxy paints that are suitable for use with potable water are widely available and due to the non-reactive nature of epoxy, it should leave the water taste-free and safe.

Things You'll Need

  • Breathing mask (if using a spray gun)
  • Protective gloves
  • Protective goggles
  • Epoxy primer
  • Roller, brush or spray gun
  • Low-speed electric drill equipped with mixing paddle
  • Two-part epoxy paint
  • Paint thinners
  • Put on your breathing mask, protective gloves and goggles and then check that the structure of the tank is sound and free from holes or gaps from which water could escape.

  • Prepare the inside surface of the tank by removing any dust, dirt or grease that is present.

  • Prime the inside of the tank using an epoxy primer that is recommended for use with your epoxy paint. Apply it with a roller, brush or spray gun.

  • Open the two separate parts of the epoxy paint and stir them well. Use a mixing paddle attached to a low-speed electric drill.

  • Mix the two parts of the epoxy paint, following the instructions that came with the product. The reaction in the paint begins immediately, so start painting swiftly before the paint gels and becomes unusable.

  • Coat the inside surface of the tank with a liberal coat of paint. Pay particular attention to any corners or hard to reach places to ensure the entire surface is covered.

  • Apply a second coat of paint, but not before allowing the first coat sufficient time to dry. This is often between six and 24 hours, but follow the manufacturer's directions.

  • Fill the tank with water after the paint has fully cured. This is usually about a week, but read the instructions on the product for the cure time.

Tips & Warnings

  • Estimate the surface area carefully to ensure you have enough paint for the job. Follow the guidance on the product’s instructions.
  • Curing times vary according to temperatures because temperature affects the reaction in epoxy.
  • Use a spray to apply epoxy paints for a more even finish.
  • Clean your equipment right after use. The paint hardens quickly, making the equipment useless.


  • Photo Credit Blue Water Tower image by Jim Mills from
Promoted By Zergnet


You May Also Like

Related Searches

Read Article

Make an Ikea Lack Table Look Expensive With This Cheap Hack

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!