With all the benefits of the Pool Frog Model 5400 in ground Fresh Mineral Water pool system and the added value of a larger chlorine pac that lasts longer on pools up to 40,000 gallons, you get more time to enjoy your pool. The Frog's No-Touch Fresh Mineral Water system, controls bacteria using a combination of minerals and reduced chlorine levels, keeping your water clean and clear for weeks at a time with no daily dosing or heavy chlorine odors because chlorine use is reduced by up to 50%. Don't spend hours sanitizing and cleaning your pool, when the Pool Frog XL Pro does the work for you, while you and your family experience an endless summer.