Pink-pigmented, forms a heavy, protective slime coating providing the organism with an unusually high level of protection, methanol consuming, oftentimes found WITH White Water Mold
that is very resilient against halogen-based (chlorine, bromine) as well as non-halogen sanitizers or germicides and can remain a contaminant even after treatment

this is NOT a biguanide (Baquacil or Soft Swim) problem ONLY

bacterium has an affinity for the matrix that exists on the surface of PVC plastics; it will attach itself to & inside of the matrix, allowing it to re-contaminate long after it appears that it has been destroyed (includes pool toys, floats, ladders, steps, fountains, automatic pool cleaner parts, skimmer baskets, weirs, directional fittings, garden hoses, etc.)  Here's more about biofilms.

small quantities can lead to a re-establishment of the problem

caused by improper water & pool maintenance, environment, poor circulation

prefers areas that are "dark" (not exposed to direct sunlight) & with "slow moving" water
** in another industry, medical technology, this bacterium occurs regularly in laboratory tubing

Pink slime is often categorized as a form algae but, in fact, it is a bacterial growth. It has the ability to form a resistance to minimal levels of chlorine, but the longer it is allowed to grow the more resistant it becomes. Successful eradication of pink slime requires early detection and diligent effort.

Look for pink slime to develop in remote hiding places in your pool; inside the skimmer, behind the light, underneath ladder treads, around return fittings, and inside automatic pool cleaners.

Pink Slime & White Water Mold ARE NOT CAUSED BY USING BIGUANIDES (Soft Swim, Baquacil, Polyclear, etc.)!
It is an environmental issue.

For further causal information please click here

Prevention:
Prevention of "pink slime" is preferred over treatment. Follow these steps to help prevent pink slime:
1. Physically brush & clean ALL Pool surfaces weekly, including ladder steps (especially underneath each step) & rails
2. Expose ALL pool surfaces to as much sunlight as possible (sunlight & UV are natural oxidizers)
3. Remove the lid from the skimmer to allow sunlight into the basket for several hours each day ** INGROUND POOLS MUST USE EXTREME CAUTION in doing this in order to avoid a person falling into or otherwise injuring themselves due to an open skimmer.
4. Regularly add oxidizing chemicals into the skimmer to purge & clean the filtration lines of any bio-film*
5 .When adding make-up water from the garden hose, allow the water to run for 2 to 3 minutes before putting the hose into the pool.
6. Regularly clean pool toys & floats (use Stow Away)
7. Regularly clean pool solar blanket (use Stow Away)
8. Chemically clean pool filter every 4 to 6 weeks (use Strip Kwik, Kleen It or Soft Swim® Filter Cleaner)
9. Add regular Maintenance dosages of "Shock" & Algicide every 2 to 3 weeks as prescribed.
10. Use Optimizer Plus as a preventative measure
11. Run the filter a minimum of 12 hours daily to prevent "dead spots" in the pool
12. Remember to clean & rinse the brushes, hoses & vacuums that you use to clean the pool 13. Leave as much of your pool equipment exposed to the sun
14. Keep the water balanced at all times. Recheck after heavy usage or rain or large "top-offs" of new water. Water balance refers to Free Available Sanitizer level, pH, Total Alkalinity, Calcium Hardness.

Treatment:
Treatment of "pink slime" MUST BE QUICK AND TOTAL! DON'T SKIMP!
Clean all pool & affected surfaces as prescribed above.
2. Physically clean & remove all visible "pink slime"
3. Add an initial dosage of algicide to the pool*
4. "Shock" the pool with a triple or quadruple dose*
5. Run filter 24 hours daily until water is clear & halogen or peroxide levels are maintained at a "higher" level*
6. Chemically clean the filter
7. Bring in a fresh water sample about 4 days later for a retest & evaluation
8. Maintain Optimizer Plus levels
9. Maintain good water balance of pH, Total Alkalinity & Calcium Hardness

To "cure" the problem, take a look at AquaFinesse Pool Pucks.