There's a song about TROUBLE. Troubleshooting is my favorite thing to do because most pool dealers or "experts" look at treating symptoms; getting to the root cause & solving the actual problem is what's called for!
Let's briefly look at:
Purple or Copper Cyanurate is caused when the Cyanuric Acid (chlorine stabilizer or conditioner) is allowed to become "high" or over 100 ppm and it then reacts with any copper that may present in the water. (Why I am so adamant about proper water testing & analysis.)
Purple Cyanurate is a chemical/mineral imbalance problem. It is NOT an "organism" or algae problem.
Furthermore, it can appear that the staining is similar to "crystals". Purple Cyanurate can not be easily scrubbed, scraped or removed. It must be treated chemically.
Purple Cyanurate is most often seen in the spring at pool opening. Although it has been "noticed", cooler water (under 68 degrees Fahrenheit) helps this reaction more readily occur.
Purple or Copper Cyanurate is further made worse by the following water balance issues:
When all of these factors come together, you will experience the staining that you see in the picture. THIS IS NOT PINK SLIME!
Prevention of "Purple or Copper Cyanurate" is preferred over treatment. Follow these steps to prevent Copper Cyanurate:
Only use copper based algaecides when treating severe algae problems.
Phosphates & Nitrogen are 2 naturally occurring elements in nature. Phosphorous is a mineral & nitrogen is a gas. In nature, they don't cause or contribute to pool problems. However when they are "added" to the pool water, problems can arise -- especially in a poorly maintained situation.
The two most significant problems are moderate to severe algae blooms and chlorine demand. Both elements are essentially set up as a buffet table for any algae to just come, eat & thrive.
Phosphates typically come into the pool from "un-natural" sources such as lawn care products; fertilizers, sprays, etc. These lawn care products can be brought in from people walking on freshly treated areas where they are literally walked into the pool. They can also "drift" in when sprayed or just due to a windy day. Remember, phosphates can come from your yard, your neighbor's yard or even from someone you don't even know who lives 3 blocks away.
More significantly, are the "natural" sources of Phosphates: basically, anything dead. Shower before entering the pool to minimize dead skin cells on your body. Plus, add in dead hair, dead leaves or grass, urine (everyone leaks a little bit), pets that may use the pool (read more here). And then there are the bird fly-overs. Sorry to be indelicate, but bird poop will be a serious trial for any pool owner!
1 Kilogram of phosphates can aid in producing up to 500 kilograms of algae (Panda.org).
Although difficult to completely eradicate, phosphates can be controlled by using phosphate removers such as ActivNzyme, an enzyme cleaner & phosphate remover. Keeping phosphate levels low can aid in controlling algae (phosphates are a natural food source for algae).
Many pool experts dismiss phosphates almost all together. PoolSpaGuru's response is: don't go crazy, but if you can remove one more stress point or one more cause to potential water problems, why not take action? Removing phosphates certainly will not hurt anything. And may prevent a cumulative affect costing you, the pool owner, time and money.
Nitrogen can also come into your pool from lawn care products, but more typical, it's a case of sweat (shower before using the pool), urine (use the facilities before going into the pool) or other types of ammonia (ammonia is comprised of Nitrogen & Hydrogen - NH4). If your local water supplier is using chloramines to sanitize the water, then large amounts of ammonia & therefore nitrogen are getting into the water. Algae loves both nitrogen AND phosphates (phosphorous).
Here's the typical scenario with Nitrogen. Nitrogen enters the water & combines with oxygen to form Nitrites (NO2). The nitrogen will typically take the oxygen from the HOCl (hypochlorous acid - the form of chlorine that kills bacteria & algae) thereby causing a Chlorine Demand. You will have a difficult time maintaining chlorine, algae will thrive, the water will become cloudy, etc. Once the nitrites have taken on more oxygen & become Nitrates (NO3), they are there to stay. The only way to remove Nitrates from the water is to drain & refill with fresh water that is hopefully not contaminated with Nitrites. Shocking & oxidizing will help to a certain degree. Nitrates (NO3) you can live with, Nitrites (NO or NO2) are the problem causers.
With either Phosphates, Nitrites or Nitrates present, as long as a good, solid chlorine or bromine level is maintained, there normally isn't a problem. However, when the chlorine is stressed out due to high bather loads, parties, rainstorms, etc. or if there is an existing chlorine demand problem, phosphates & nitrates just feed right into any algae present & the problem worsens significantly.
Treating the problem:
To Make Your Pool Care Experience Fantastic, add Optimizer Plus® to create a level of 30 ppm to 50 ppm. Using Optimizer® Plus will significantly reduce your Smart Stick® consumption and provide the wonderful, soft feel that is associated with biguanide treated pools.
Enzymes are special, naturally occurring (although there do exist man-made and natural enzymes) molecules that "eat" or "digest" organic waste that is not easily filterable or can be readily oxidized. Enzymes are nature's way to break down many organic compounds. You'll find enzymes in your own body! They break down fats and sugars. Insulin is a kind of enzyme.
Enzymes come in various "types" that are suited for specific jobs. The enzymes bind to the organic waste and chemically break the waste down. The final "waste of the waste" is carbon dioxide (CO2) and water.
As you can imagine, turning organic waste in swimming pools into CO2 & water is a great thing! Those 2 components are then reabsorbed back into the pool or spa water. Your sanitizer (chlorine, bromine, biguanide, etc.) can concentrate on its job - killing bacteria. Oxidizers or shocks can do their job - oxidizing contaminants that cause chloramines. Algaecides are not as stressed because algae is not being "fed" by these organic wastes.
Natural Enzymes vs. Synthetic Enzymes - Whether enzymes are natural or synthetic, they come from the world around us. Here's the difference between the two in a broad sense is: synthetic or man-made enzymes are manufactured or cooked and blended. They tend to be specific in their "feeding"- they will eat only specific wastes such as fats and oils. Man-made enzymes tend to be much less stable than natural enzymes.
Natural enzymes are "naturally" formed through the process of fermentation. Fermentation produces a "broad spectrum" enzyme that is dramatically more stable and able to "eat" a significantly wider range of organic wastes. Natural enzymes such as those found in ActivNzyme will remove all of the following kinds of organics that are often found in swimming pools: human waste, waste fuel oil, deodorants, soaps, bird droppings, sweat, shampoo, body oils, cosmetics, hair spray and other hair treatments, body lotions, pipeline anti-freeze residue, air borne pollution, tree sap, organic fillers, and more. The more organic, swimmer and environmental waste that can be "consumed" and eliminated, the less potential problems that you and your pool will face.
Natural enzymes consume the organic wastes that contribute to scum lines that eventually (quickly) become biofilms that are a breeding ground for bacteria and algae. Build-ups of scum lines are not only visible at the water line, but in the skimmer, pool pipe lines, and even into the filter itself; fouling filter grids, cartridges, and even the sand causing shortened filter runs and media life.
Enzymes can be used in ALL swimming pools using ANY sanitizing system - chlorine, bromine, Soft Swim®, Baquacil®. Enzymes used with ionizers such as Nature2® or Pool Frog® are a terrific idea because they keep the "beads" in the ionizing canister cleaner by consuming the organic waste that can foul the canister.
Regular use of ActivNzyme on a weekly basis will help prevent the organic component of water molds and slime (imagine a pool without pink slime or white water mold!). When you couple ActivNzyme with BioGuard® Optimizer Plus® and AquaFinesse, you have a system that can't be beat. Why? Read more here.