Key 2 - Filtration
Now that the water is circulating properly, good filtration removes dirt, debris & even distinct large bacteria & algae. Sand filters take off the largest particles, Cartridge filters take off smaller particles & De filters take off the smallest.
Microscope
Let's look at the 3 types of filters & how they work.
Sand filters. All sand filters have 3 things in base as to their performance: 1. They all use sand (some older filters may use a mixture of sand & gravel). 2. Dirty water enters in the top of the filter tank & flows down straight through the sand which filters out the dirt & debris (down to a size of about 25 - 40 microns - graphic dirt & debris). 3. Cleaner, filtered water is collected at the bottom of the filter tank & pushed out of the filter & returned to the pool.
Sand filters are the oldest form of pool filtration or water filtration for that matter. Even old civilizations used sand as a filter to cleanse water & help make it more potable (drinkable).
Sand filters have been the most base filters used in the swimming pool industry until recently. These filters are great when using non-chlorine sanitizing products such as biguanides (i.e. BioGuard Soft Swim or Arch Chemicals Baquacil). For most people, sand filters will perform a very adequate job.
Drawbacks: more time needed to filter out fine particles; lots of water (sometimes hundreds of gallons) is "wasted" when backwashing or cleaning the filter by reversing the flow of water inside the tank; sand is heavy.
Care of Sand filters: Backwash only when needed - a dirty sand filter pulls out a finer particle - ordinarily no more than once a week. Chemically clean the filter about 2 times per season (after preliminary cleaning & at mid season) to break up & take off accumulated greases, oils & dirt that has become embedded in the sand. Change the sand about every 3 - 5 swimming seasons (one season equals about 4 - 6 months) - sand crystals lose their "sharpness" & are not as well able to trap dirt & debris. Please quote the note on Chemical Cleaning below.
Cartridge Filters: Like sand filters, all cartridge filters have 3 things in common: 1. They all use some type of pleated fiber cartridge. 2. Dirty water enters in to the filter tank & flows straight through the cartridge which filters out the dirt & debris (down to a size of about 10 - 20 microns - much smaller, but still graphic dirt & debris & some algae). 3. Cleaner, filtered water is collected on the other side of the cartridge & pushed out of the filter & returned to the pool. Some folks consideration a cleaner divergence compared to sand filters.
At one time, cartridge filters were only favorite in the sunbelt areas. Today, they are used in all parts of the country on all kinds & styles of pools. Cartridge filters can be used with any pool sanitizing system. Because of their relatively large filter surface area (the pleated fiber material can be as large as several hundred square feet as compared to under 4 square feet in the largest residential sand filter), cartridge filters commonly take a long time to get dirty between cleanings. A properly sized filter may only need to be cleaned 2 or 3 times per season. When sized right, less vacuuming may be needed due to the finer filtration.
As with all filters, sizing it properly is critical. Never undersize. Never. This is a true case for the axiom, "you get what you pay for." An undersized cartridge filter May initially do the job, agreeing to the sizing charts, but in short time you will be disappointed in the performance of the filter and in the amount of work you now need to do.
Drawbacks: proper sizing of the filter to do the proper job. Trying to use an aboveground filter on an inground pool. Filter must be disassembled & cleaned about once each month.
Care of Cartridge Filters: Clean only when needed. ordinarily about once each month. Cleaning is accomplished by taking the filter apart & hosing off the accumulated dirt & debris from the cartridge. Chemically clean 2 times per season to (after preliminary cleaning & at mid season) to break up & take off accumulated greases, oils & dirt that has become embedded in the cartridge material. Replace the cartridge about every 3 - 5 swimming seasons (one season equals about 4 - 6 months). Please quote the note on Chemical Cleaning below.
De Filters: De or Diatomaceous Earth filters offer the finest filtration available. De filters use grids or "fingers" called septums that hold De (fossilized microorganisms) that has the properties of a fine but gritty powder. De filters have the ability to filter particles as small as 2 - 5 microns in size (the size of algae & even some large bacteria).
Water goes into the filter & passes straight through the De coated septum. Under a microscope, De looks like dinky sponges with tiny holes & nooks & crannies that trap all kinds of stuff. The clean water is then collected & returned back to your pool.
In many places you can or are urged to use De replacements, such as Aqua Pearl, which are lighter in weight & more biodegradable than De. Especially compared to sand filters, you don't get just filtered water, you get polished water.
De filters eliminate many pool care problems because of the superior filtration. A De filter has the ability to take a dark green, algae encrusted pool & turn it into a crystal clear paradise in a matter of a few days. Many pool owners consideration how less often they "need" to vacuum the pool. However, there is more care needed in maintaining a De filter.
Drawbacks: De filters tend to clog up easier - partially a function of the fine filtration ability. If you have a easily dirty pool, the filter may clog up every join of hours & you may have to Change the De. That's normal. However, you will reap the clarity results in much less time. The other drawback is the waste or used De. In many municipalities it is considered a hazard waste material & therefore needs to be treated as such. Check your local authorities for details.
Care of De Filters: Clean only when needed. Some De filters come with backwash valves while others need to be "bumped". Physically clean (2 times per season) the filter by taking the filter apart & hosing off the accumulated dirt & debris from the grids or fingers - backwashing or bumping may not fully take off the used De. Chemically clean the filter 2 times per season (after preliminary cleaning & at mid season) to break up & take off accumulated greases, oils & dirt that has become embedded in the septum material. If ordinarily chemically cleaned, the grids should provide a life of, 7 years or more. Please quote the note on Chemical Cleaning below.
Filter your water for 8 to 12 hours every day from opening to closing. Use a timer so that you don't forget and save money. By the way, for the best filtration, be sure to chemically clean your filter about twice each season to take off accumulations of greases, oils & other swimmer and environmental waste that clog your pool filter & that disposition backwashing & rinsing will Not remove.
Why you need to Chemically Clean your filter: As noted just above, chemical cleaning of your filter aids removing greases, oils & other swimmer and environmental waste that will soil your filter and shorten its life. Normal, regular backwashing & rinsing will not take off these wastes. Here's a join of analogies that will help you understand the importance of chemical cleaning: do you use shampoo on when you wash your hair or do you just rinse it? Without shampoo, your hair would be pretty matted & dirty after a join of weeks. How about dirty clothes? Do you only rinse them out in the washing machine or do you add detergent to release & help take off the dirt & greasy stains? The same thing goes with your pool filter. How do you chemically clean a filter? That's easy. Use filter cleaning products such as BioGuard® Strip Kwik® that is used when you can soak your filter (soak the elements or it can be backwashed into a sand filter) for a several hours. Spray on products such as BioGuard® Kleen It® work swiftly to take off ground in dirt & oils.
Filtration - Second Key to Good Pool Care
Related : Measurement Guide Top 10 Tablet PCs KVM Switch Measurement Guide
