To size the filtration system correctly, it is necessary to determine the required turnover rate for the pool, as well as verify the proper filtration rate (typically 57 litres per minute [lpm] [15 gallons per minute (gpm)]/930 cm2 [1 sf] for a commercial pool). For example, a 757,082-L (200,000-gal) pool that needs a six-hour turnover would require a 2105-lpm (556-gpm) filtration rate. Therefore, the pump needs to provide this filtration rate (at least) at the given total dynamic head (TDH) and the filtration system would need to be sized to handle this flow rate. Doing this will increase the filtration system’s efficiency.
Incorrect chemical diagnosis
There are many different chemicals available in the marketplace that are used to keep pool water clean and clear; however, one of the biggest mistakes a service technician can make when diagnosing a water treatment issue is failing to check the pool filter first.
“Whenever I am presenting a seminar on chemicals and pool water treatment, I always start by saying, “Water clarity is only as good as the filter will allow it to be,” says ProTeam’s regional sales manager, John Bokor. “Pool chemicals can resolve many different water quality problems, but if the filter isn’t working properly, neither will the water treatment program.”
During the summer, the most frequent call service technicians get from pool owners is that their water is cloudy. Most respond to this problem by telling the customer to simply add a clarifier; however, a clarifier will not clear the pool water if the filter is gummed up and not filtering properly.
Sand filter best practices
Sand filters are still one of the top filtration systems used throughout the industry. That said, they need to be monitored closely to ensure the media inside the tank stays smooth and does not solidify. If this happens, the filter’s efficiency will degrade severely as water will not be able to pass through the sand. If this happens, the service technician should turn off the pump and open the filter casing to inspect the sand to determine whether the media needs to be changed or simply backwashed.
Maintaining the filter valves is also imperative. Failing to do so may result in the client having to replace the gaskets, as they can be a source for water loss.
It is important to know how to keep a sand filter functioning properly. One way to do this is by using a filter cleaner additive as it gives sand filters an extra boost to remain effective.
Another good tip for sand filter maintenance is to add a dry clarifier to help remove fine particulate. The dry clarifier coats the sand bed, filling in any nooks and crannies in the media, and is then simply washed out of the filter during the backwash without leaving any residual.
“Using a dry clarifier increases filter efficiency by penetrating the sand with a polymer formula and restores water quality after heavy rain and/or bather loads,” says Bokor. “The product attracts all matter as small as two microns and captures it in the filter.”
Terry Arko, a water treatment specialist with NC Brands/SeaKlear, says using a clarifier product can be an invaluable aid for sand filtration. Depending on the product being used, it can enhance the filter’s ability to trap particles down to 0.5 microns.
“These products are perfect for commercial facilities to keep pools clear and clean even during times of peak bather load,” adds Arko.
According to Deakin, when it comes to sand filters, they always take a proactive approach and replenish the sand every five to 10 years.
