Pool and Jacuzzi Filters Selection Tips :
Want to use swimming pool and hot tub filters to improve the quality of water in your swimming pool and hot tub but you are not sure of type, model, brand, price, and specification...
Pool and Jacuzzi Filters Selection Tips :
Want to use swimming pool and hot tub filters to improve the quality of water in your swimming pool and hot tub but you are not sure of type, model, brand, price, and specifications that suit your purpose? Read on to find the answers to all your questions on price, technical specifications, and the best swimming pool and hot tub filters on the market.
The treatment and improvement of the pool or jacuzzi water start with it passing through a filter.
Water filtration is a physical process that only removes the particulates and impurities from the water.
Water filters are even capable of eliminating some of the bacteria in the water, but it must be emphasized that filtration is different from disinfection. Overall, three types of filters, namely the sand filter, the diatomaceous filter, and, the cartridge filter, exist for pool water treatment, which are readily discussed.
1. Diatomaceous Filters
- Thanks to their ability to absorb particulates sized 10 to 20 μm, diatomaceous filters are among the most efficient pool and jacuzzi filters and are suitable for both public and private pools. These filters incorporate diatomaceous earth in variable amounts depending on the filter capacity. The diatomaceous earth is the fossilized remains of microscopic siliceous-shelled, marine plants that provides an ideal, chemically-neutral filter.
- Diatomaceous earth is not poured into diatomaceous filters directly but through a strainer. If the pressure on the diatomaceous filter gauge exceeds the usual limits, backwashing becomes necessary—which requires the filter to be recharged with diatomaceous earth afterward.
2. Sand Filters
- Sand filters—in particular, the metal types—are heavier than their diatomaceous or cartridge counterparts. The weight is often due to the incorporation of silica or sand for pool and jacuzzi filtration.
- Sand filters for pools and jacuzzis are manufactured with metal, fiberglass, or composite tanks. Filters with metal tanks can withstand high pressure and are available in large sizes, but are prone to rust, which can contaminate the water. As a result, the filters require proper maintenance and must be coated on the inside with suitable epoxy paint.
- Sand filters with an FRP fiberglass or composite tank solve the rusting problem but support a lower pressure and a smaller volume of sand, which can be worked out by employing several of them in parallel for large pools.
- Typically, 60% of the sand filter is filled with silica or sand, which is available in two types.
- The processed sand, which is made of a special nanopolymer and comes in 25 kg packages. The service life of this type of sand is 10 times the common sand, which also improves the filtration.
- Common sands that are available in three types, namely coarse, fine, and medium. This grade of sand comes in 40 kg bags. Often, the sand filter is filled with 75% fine grain at the bottom, 15% medium grain in the middle, and 15% coarse grain at the top (see the picture below).
- In modern sand filters, silica is used as the filtration medium. High-quality silica is a bright, white powder that is produced by crushing silica stones. After crushing the stones, the resulting grains are sieved and marketed in various grain sizes. The best and highest-quality silica for pool filters in Iran is the Hamedan silica which is entirely white and without brown or yellow veins.
2-1. Types of Sand Filters for Pools
A. Open (gravity) sand filters
B. Pressurized sand filters.
A. Open sand filters
- These filters are among the oldest types of sand filters. The silica bed in this filter is exposed to open air, and the polluted water, driven by its weight, passes the bed—quite slowly—without pressurization. Hence the name open sand filters.
- This type of filter is typically used for large-scale filtration, such as the filtration of municipal water and wastewater.
B. Pressurized sand filters
- In a pool filter, the silica is contained in a tank, and the jacuzzi or pool water is pumped into the silica bed for filtration. Water moves at a higher speed in these filters in comparison to open filters.
- The closed tank filter is filled with three or four different grain sizes. At the bottom of the sand filter, coarse-grained (5–8 mm or 3–5 mm) silica is used. The size depends on the type and size of the nozzle at the bottom of the filter. Medium-grained sand (1–3 mm) is used in the layer on top. This layer prevents the intrusion of finer silica grains from the top layer. Next, on top, fine silica with 0.2–0.8 mm grains is used. Water filtration and the absorption of particulates are mainly carried out at this layer, and the other two layers serve to keep the finer sand particles in place.
- In some sand filters, a layer of coarser silica is applied on top of the fine grains to prevent the 0.2–0.8 mm, light-weight sand particles from leaving the filter during backwash.
- The typical pressurized sand filter tank is made of fiberglass which has its advantages over metal, including limited wear—especially in humid regions—and disadvantages, such as lower temperature and pressure tolerance.
2-2. Sand Filter Calculations
- Sand filter calculations are fairly simple for a pool or jacuzzi. Calculations depend on the intended use of the pool or jacuzzi (private, public, competition, etc.), whether it is indoor or outdoor, the pollution load (number of swimmers per 24 h), and the working hours.
- The calculations are similar for a pool and a jacuzzi, but the working temperature must be considered when selecting a filter as the water is maintained at 40–45 °C in a jacuzzi and can even exceed that in case of fluctuations or likely controller malfunction.
- The first step in the calculations of a sand filter is to calculate the volume of the pool or jacuzzi. If the pool or jacuzzi is rectangular, the volume (m3) can be obtained by simply multiplying its length by width by average depth (m).
- L: Length
- W: Width
- R: Diameter
- A.D: The average depth, that is (the minimum depth + the maximum depth)/2.
All sizes are in meters, except for the volume that is in cubic meters (m3).
The return period or the water recirculation rate must be obtained—with the help of the table below—to carry out the calculations.
- The return period or the water circulation rate is, in fact, the time required for the entire volume of water in the pool to circulate the filtration system once. However, this by no means signifies that the entire body of water has passed the sand filter. Based on the experiments, nearly 60% of the water is filtered on average. However, after 7 or 8 cycles, it is safe to say that all of the water in the pool has been filtered.
- Discharge through the filter can be obtained by dividing the volume of the pool by the circulation rate or the return period. Most catalogs report the sand filter discharge, whichcan be used to select the suitable filter. However, for more accurate calculations, or in case of not having access to the manufacturer’s datasheets and catalog, the sand filter diameter can be obtained as follows.
- To calculate the diameter of a metal sand filter, a discharge of 5–5.1 gal/min can be assumed for every square foot of the filter area. This rises to 15–20 gal/min for fiberglass pressurized sand filters. The filter height is assumed 1–1.2 times its diameter.
3. Cartridge Filters
- Capable of removing 2–7 μm particulates from water, and usable in residential hot tubs, small hydrotherapy pools, small indoor pools, and endless pools.
- The cartridge filter integrates lenticular filter sheets and is easy and quick to clean.
- The cartridge filters can also be used on manual pool vacuum cleaners of up to 2 hp. The filter prevents wasting water by allowing the user to filter the water and return it to the pool while sweeping the basin.
- The main reasons that cartridge filters can be used on manual pool vacuums are their light weight, small size, and high filtration capacity. However, the filter is not suitable for over 2 hp electric motors.
Pool and Jacuzzi Filters Selection Tips
- The most important thing to note when selecting the size and capacity of the jacuzzi filter is the volume of water in the basin. The selected filter must be capable of filtering the entire pool within 6 to 8 hours.
- Before selecting the filter, learn the maximum working pressure it can withstand. The working pressure is variable depending on the model and structure of the filter. Note that the recommended time for the complete filtration of the pool is under 6 hours for outdoor pools and 8 hours—at most—for indoor pools. Calculations are slightly different depending on the type of the filter (sand, diatomaceous, cartridge).
- Other significant aspects of this evaluation—in addition to the filtration capacity—include whether the head and discharge of the pump match, as well as the pressure drop across the filter, which depends directly on the type of filter and the type and amount of sand in the filter.
- The sand and diatomaceous filters are equipped with labeled, five or six-position valves to facilitate their operation, but it must be noted that the pump must be switched off before changing the position of the valves, otherwise the valve is damaged, which voids the warranty.
- Important note: before placing an order for a pool filter, note the size and dimensions and plan the layout to make sure there is enough space to install the equipment properly.
After all, if you had more questions to decide for buying different types of Pool and Jacuzzi filter, you can contact to DamaTajhiz company and ask your questions from sales consultant of pool, sauna and jacuzzi equipment department through this internal numbers: 103 – 105- 106
Placing an Order and Warranties for Pool & Jacuzzi Filters
- Offering best price guarantee for all products, the prices for pool & jacuzzi filters presented by DamaTajhiz are up-to-date and discount-included (see Best Price Guarantee at DamaTajhiz.com).
- At DamaTajhiz.com, we provide all the information you need, as well as guaranteed unbeatable prices, for several models of pool & jacuzzi filters from reliable manufacturers, with original warranties, to bring you the thrill of an ideal, intelligent purchase.