Removing hard water stains

You finally scored that awesome tank at a killer price but now how do you clean it??

If the tank is simply dirty but no actual build up on the glass, the cleaning process is pretty straight forward.

A mild detergent can be used with hot water to wash away dirt and grime.

Use a mild bleach solution 1:10 ratio to sanitize the tank in case of parasites or disease. Follow up with a thorough rinse with water and then white vinegar. Allow to air dry 24 hours.

Dealing with stubborn build up on the glass is more challenging. Some stains may never come off. If the stains are only on one wall of the tank you may be able to make that the back wall of your tank. Hard water stains won’t bother your hermit crabs, only obstruct your view.

A combination of acid and abrasion is needed.

  • White vinegar
  • Lemon Juice or Lemon Essential Oil
  • Salt
  • Baking soda
  • Toothpaste
  • Food Grade Diatomaceous Earth
  • Magic Eraser or other very fine grit sandpaper – use damp
  • Razor blade

Your best option is to make a paste that you can smear on and leave to soak for hours or even overnight. All of these items require time to work.

White vinegar or lemon juice are safe natural acids. Combine with salt, diatomaceous earth, baking soda or toothpaste for grit. This will likely scratch the glass and make it cloudy so test on a small spot first. A good strong razor blade scraper can also be used with care to avoid scratching the glass.

You may have some luck with a commercial product if the build up is not too heavy:

Aqueon hard water stain remover: 

Once clean, regular cleaning of the glass will prevent build up. Keeping a squeegee handy will make clean up go quickly.

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