Pink Slime (and its “friend” white water mold) is a newer problem facing pool owners in the last 10-20 years. They occur naturally and are caused solely by a lack of proper pool maintenance and water chemistry. In fact, even non-pool owners have problems with pink slime in bathrooms, kitchens, and toilets. Have you ever noticed that pink ring around the sink? That’s pink slime.

Let’s define what pink slime is. Pink slime is a naturally occurring bacterium (from the newly formed genus methylobacteria). The pink lime is NOT a form of algae, it is animal, not vegetable. It has a pink or red pigmentation and forms a thick protective layer of slime that provides the organism with an unusually high level of protection. Pink slime consumes methanol (a waste gas) and is often found WITH white water mold. This organism is highly flexible and resistant to halogen-based (chlorine or bromine) as well as non-halogen-based disinfectants or germicides, and can remain a contaminant even after treatment.

Although initially found in pools treated with biguanides (Baquacil, Soft Swim, Polyclear, etc.), it is now seen in any and all pool environments. This is NOT a problem of biguanide ONLY nor is it CAUSED by the use of biguanides.

Pink slime bacteria have an affinity for the matrix that exists on the surface of PVC plastics; will adhere to and within the matrix, allowing it to become re-contaminated long after it appears to have been seemingly “destroyed” (includes pool toys, floats, ladders, steps, fountains, automatic pool cleaner parts, skimmer baskets, weirs, directional fittings, garden hoses, etc.). Small amounts of pink slime can lead to reestablishment of the problem. It is caused by improper water and pool maintenance, environmental factors, and poor circulation. Pink slime prefers areas that are “dark” (not in direct sunlight) and with “slow-moving” water. In another industry, medical technology, this bacteria is regularly found in the laboratory vat.

Look for pink slime under stair treads, behind the skimmer weir, on the bottom of skimmer baskets, on pool directional returns, in pool underwater light niches, and on pool housings. lights. If you find that the pool simply doesn’t contain the chlorine, bromine, or even hydrogen peroxide that is used in biguanide-treated pools, look to pink slime.

After regular monitoring of homeowners’ pools affected by pink slime, here are some common threads:

• Many, but not all, affected pools have “smaller size” cartridge filters. (i.e. using a 75 sq ft filter on a 24 ft Rnd above ground pool or a 90 sq ft filter on a 15 x 30 inground pool).
• Affected pools receive 6 hours or less of direct sunlight on pool surfaces.
• Pool owners always leave the solar blanket on AND do not chemically clean the blanket the recommended 2 times a year to remove built-up biofilm.
• The “shock” or oxidation of the pool water is not done with the recommended instructions on the label. For example, instead of shaking the pool every week or two, that task is neglected because the water “looks good.”
• Rainy pool seasons see a dramatic increase in cases of pink slime.
• Customers regularly add fresh water from their tap without letting the hose run for a couple of minutes (the pink slime is already present in the garden hose and transfers to the pool).
• Pools with sand filters do not change the sand every 2-3 years AND do not chemically clean the filter sand 3 times per season (once every 6-8 weeks).
• Most recent observation: Most of those affected seem to use publicly treated drinking water. Pools filled with well water appear not to be as severely affected.
• Affected pools do not receive as meticulous chemical maintenance (water balance, use of borate additives like BioGuard Optimizer Plus or Proteam Supreme, regular cleaning) as clean pools.

Another observation is that many water companies across the country, in partial response to “consumer calls” to “get rid of chlorine in drinking water,” are now using monochloramines to treat their water (over the last 15 to 20 years). Monochloramines do an essentially good job of treating pathogens in drinking water, however some of the non-pathogenic organisms may be surviving. Unfortunately, there is only experimental or anecdotal evidence.

Prevention of “pink slime” is preferred to treatment. Follow these steps to help prevent pink slime:

1. Physically brush and clean ALL pool surfaces weekly, including ladder rungs (especially under each rung) and rails
2. Expose ALL pool surfaces to as much sunlight as possible (sunlight and UV rays are natural oxidizers)
3. ** IN-GROUND POOLS MUST USE EXTREME CAUTION when doing this to prevent a person from falling or being injured due to an open skimmer.
4. Regularly add oxidizing chemicals into the skimmer to purge and clean the filtration lines of any biofilm (be very careful if you do this. Add chemicals slowly and remove ANY and ALL objects, including slow dissolving chlorine tablets or sticks, to avoid a possible chemical). reaction like an explosion.
5. When adding make-up water from the garden hose, allow the water to run for 2-3 minutes before placing the hose in the pool.
6. Regularly clean pool toys and floats (use BioGuard Stow Away to fight mold)
7. Regularly clean the pool solar blanket (use BioGuard Stow Away)
8. Chemically clean pool filter every 4 to 6 weeks (use Strip Kwik, Kleen It, or Soft Swim® Filter Cleaner). This is a very important step regardless of the type of filter; sand, DE or Cartridge.
9. Add regular maintenance doses of “Shock” and Algaecide every 1 to 2 weeks as prescribed (3 to 4 weeks in bguanide groups).
10. Use borate products such as BioGuard Optimizer Plus as a preventive measure (borates, when used correctly at a rate of 50 to 80 ppm, allow the disinfectant to clean rather than disinfect and prevent algae growth).
11. Run the filter a minimum of 12 hours daily to avoid “dead spots” in the pool.
12. Remember to clean and rinse the brushes, hoses and vacuums you use to clean the pool
13. Leave most of your pool equipment exposed to the sun (sunlight is a natural oxidizer)
14. Keep the water balanced at all times. Recheck after heavy use or rain or large “fill-ups” of new water. Water balance refers to the level of available free disinfectant, pH, total alkalinity, calcium hardness.

Treatment of “pink slime” MUST BE FAST AND TOTAL! DO NOT CLIMB!

Clean entire pool and affected surfaces as above.

Physically clean and remove all visible “pink slime”

Add an initial dose of algaecide to the pool

“Shock” the pool with a triple or quadruple dose

Run the filter 24 hours a day until the water is clear and the halogen or peroxide levels remain at a “higher” level.

Chemically clean the filter. Simply rinsing or backwashing the filter will not remove accumulated greases, oils, and other contaminants from the filter and filter tank.

Have your pool water professionally tested and tested. Look for a pool company that knows what they’re talking about and isn’t afraid to tell you the truth about the problem.

Maintain Optimizer Plus (or other borate product) levels

Maintain a good balance of pH, total alkalinity and calcium hardness in the water

The longer you let pink slime sit, the harder it will be to cure.