Physical Factors Include:
I. Filtration
Filtration is the term used to refer to the mechanical cleaning of pool water. It is a key element in pool water maintenance that is frequently overlooked in its importance. When operating properly, a filter will remove virtually all particulate matter from the water. These particles of dirt and debris are the result of environmental fallout or are left behind by the bathers and, when not properly filtered out, will cause the water to become hazy or cloudy.<
The filter will play a very important role even when cloudiness due to a chemical imbalance occurs. By performing properly in removing most of the cloudiness, a fully functional filter will usually allow the water to remain clear enough for continued use of the pool. This gives the pool operator, service person or dealer time to determine the nature of the problem and take corrective action. Since the pool was reasonably clear in spite of the problem, it could remain in use without a panicked customer or need for drastic chemical adjustments.
Filter Types
There are three types of filters commonly used on swimming pools:
- Cartridge Filters
- Sand Filters
- Diatomaceous Earth (DE) Filters
While each can be effective in keeping water clean, they require proper maintenance in order to gain maximum benefit and service life. A review of how each works and an understanding of how to handle them will be of value.
II. Circulation & Turnover
Circulation refers to the process of regularly moving all of the pool water through the pump and filter system. In contrast, the term turnover is used to describe how long it takes for a given amount of water to pass through the pump. In other words, when it is said a pool has an eight hour turnover it simply means that when the pump is running it will take eight hours for the net volume of water in the pool to move throught the pump and filter system.
It is important to note that turnover does not mean that all of the water in the pool went through the pump and filter. It could be the same water over and over, which is what happens when water is not properly circulating. The growth of Black Algea can be evidence of slow or “dead spots” in the pool that occur because of poor circulation to those areas causes insufficient amounts of sanitizer or algaecide to reach those areas frequently enough to be effective.
There are several things you can do to help assure proper circulation. If the pool has a bottom or main drain, keep it open so that at least 50% of the water is being drawn through it. The skimmers then handle the rest. Adjust the return line fittings so that they direct the water flow in a generally circular patter around the pool and also aim them gently downwards to improve water mixing from top to bottom. This last point is critical in pools with no main drain or where the main drain no longer functions due to age or some other problem that is unable to be corrected.
III. Other Factors
The control of oily wastes left behind by the bathers and the general care for the appearance of pool walls, covers and equipment.
Each of these factors plays an important role that is all too often overlooked or considered unimportant when considering how much a pool will be enjoyed.
When faced with a pool problem, we have a tendency to immediately look into the water chemistry factors. Cloudy water, for example, causes us to question water chemistry when the problem may simply be due to a filtration issue. The management of the physical factors should be considered the first line of defense in the prevention of pool water problems.
There are several other areas that require attention in order to keep the pool looking inviting and ready for use.
These Include:
Clarification and Flocculation
Even though we have made certain that the filter is working properly and the circulation pattern is correct, the pool water can still appear hazy or dull. This is most often due to the build up of what is commonly referred to as micro particles in the water. These particles are so small that they simply pass through the filter media without being trapped. To make matters worse, these particles develop a negative electrical charge and since the charges are all alike, they repel one another and do not clump together, which would otherwise make them easier to filter out. The addition of a “water clarifier” will solve this problem.
A water clarifier contains a solution of positively charged particles that when added to water, will seek out the negative particles and neutralize there charges. The particles the tend to clump together and are easily filtered out. Used regularly, a clarifier will reduce maintenance, improve filter performance and enhance the appearance of the pool water.
In unusual circumstances of severely cloudy water, such as you may experience at spring opening, the use of a liquid Flocculant or “floc” can also be helpful. A floc works similarly to a clarifier; however, instead of helping to remove small particles through the filter, a flocculant coagulates the cloudy water particles into massess that settle quickly to the pool floor so that they can be vacuumed up easily.
A liquid floc can be a real benefit in clearing up severely dirty pools in a short period of time. In contrast to the use of Alum based flocs, these materials do not require pH adjustment or result in significant contamination of the water should the circulation system be erroneously turned back on before all the alum has been removed.
Control of Grease & Oils
Proper operation of filtration equipment and circulation systems will go a long way to helping assure a pleasant bathing experience. It must be kept in mind, however, that in addition to the bits of dirt and debris that are easily filtered out, the bather will also leave behind a variety of wastes that can cause other problems in general pool management.
Accumulations of body oils, cosmetics and other complex bather waste can result in the build up of these materials along the water line and in pipes and filters. This waste can cause unattractive scum lines and interfere with the performance of the sanitizer, a problem that will affect the overall appearance of the water.
While cleaning products are available for use on scum lines that will keep the water line clean and bright, it also requires that they be applied manually. Developments in the use of enzyme digestive products now allow us to not only control this waste in the water, but to prevent their build up on the walls and in equipment.
Enzymes are widely used today in both industrial and domestic applications. Many laundry detergents use enzymes to help in the breakdown and removal of stains and deep set soil. Enzymes are naturally occurring biological catalysts, which means they help increase the breakdown rate of complex compounds. In pools, specially developed natural based enzymes are used to help breakdown complex materials like oils and grease. With regular use they will take these very complex and difficult to control materials and break them down into smaller fragments that can be readily destroyed by Shock Treatment.
It is important to point out, however, that not all enzymes are well suited to pool use. As stated previously, enzymes are naturally occurring substances of biological origin. Since they are manufactured by living organisms and since chlorine and other sanitizers destroy living substances, it is important to select enzymes that can tolerate the typical sanitizer levels commonly found in pools. It is also important to understand that enzymes are highly selective in terms of what substances they will breakdown. Therefore, one must use enzymes that have been properly selected for digestion of the types of oils and greases found in pool water.
Used as part of a regular maintenance program, enzymes will minimize scum line formation and reduce the frequency for the need to clean the tile line as well as reduce the build up in pipes and equipment. In addtion, the enzyme will help reduce the build up of these organic wastes on filter media and thus reduce the frequency of cleaning as well as improving water appearance.