How to Eliminate Pink Slime and Water Mold from Your Hot Tub

There are few things more frustrating than dealing with pink slime and white water mold if you are a hot tub owner. Both of these organisms can invade and colonize your hot tub, leaving it with a disgusting, unsightly coating. Both are resistant to treatment, too, and that only compounds the problem. There is hope, though; here is how to successfully remove pink slime and white water mold from your hot tub, and how to keep it from ever coming back again:

Information about pink slime and white water mold

Pink slime is a byproduct of bacteria in the methylobacterium family. The bacteria finds polyvinylchloride (PVC) a particularly attractive growth medium, and it will stubbornly cling to this surface once established. Pink slime is not harmful to humans, but its appearance will prevent you from fully enjoying your tub. In addition, it's slimy coating can cause damage by clogging pipes, jets and filters.

White water mold is a fungus, but it often appears in conjunction with pink slime. Like its more colorful partner-in-crime, white mold is harmless, though it does create an unsightly appearance. 

Eliminate pink slime and white water mold

If your hot tub contains pink slime or white water mold, do not procrastinate when it comes to cleaning. These organisms grow fast, and they may quickly overwhelm your hot tub.

Treating pink slime and white water mold is fairly straightforward, but spa owners often fail to use a strong enough treatment. The preferred treatment for these microorganisms is an intense application of a chlorine-based hot tub shock. To shock your tub, do the following:

1. Purchase an appropriate sodium dichlor-based product. You will need 2.5 ounces of sodium dichlor granular powder per every 100 gallons of water in your tub. For example, if your hot tub's capacity is 400 gallons, 10 ounces of sodium dichlor is necessary for an adequate shock.

As a note of warning, never use sodium hypochlorite-based products in a hot tub. These chemicals are designed for the cold water environment of a swimming pool, and they can damage your tub's finish and components.

2. Remove your hot tub's filter and dispose of it.

3. Next, dissolve the appropriate amount of sodicum dichlor in a bucket of warm water. Pour the dissolved solution into your tub.

4.  Allow the water to circulate in your hot tub for at least 24 hours.

5. Drain all the water, and thoroughly wipe down all the surfaces of your tub, including the area in and around the water jets.

6. Refill the tub with clean water, and install a new filter.

Prevent pink slime and white water mold from recurring

Once you have eliminated pink slime and white water mold, you do not want it to make a reappearance. Here are some practical ways to keep your tub slime and mold-free:

  • Take a shower before entering the hot tub - when organic particles, such as dead skin cells and body oils, decompose, this process generates methane gas, a food source for pink slime. Showering before entering keeps organic contaminants out, and thus prevents your hot tub from becoming a microorganism "buffet."
  • Maintain a regular cleaning schedule - there are numerous chlorinated and non-chlorinated products on the market that can keep your hot tub's water sparkling and clean as long as you routinely use them. Each product has its own advantages and disadvantages, so be sure to carefully research them and make a decision about what is best for your hot tub. Be especially careful not to casually mix hot tub chemicals together, as some substances are not compatible with one another.
  • Cover your tub - when not in use, cover your tub with a tight-fitting cover. This will help keep out organic matter and other foreign substances that can lead to pink slime and white water mold growth.

To learn more about how to care for your hot tub, be sure to visit