Hydro-Logic Purification Systems is the leader in water purification in the hydroponic industry. Since their inception there have been a number of other companies that have entered the market but despite their marketing efforts and lower prices, they simply cannot touch the quality and service that Hydro-Logic offers. Their original line of Stealth Reverse Osmosis systems set the bar and continues to do so today. The Merlin was their commercial size reverse osmosis system, which was then replaced by the Evolution, which boasts 1000 GPD of clean, filtered water. And if that's not big enough they also have a line of commercial RO systems called Hyper-Logic that start at 1000 GPD and goes up to tens of thousands of gallons per day. For growers who only need to eliminate chlorine and other VOC's they offer the Small Boy, Tall Boy and Big Boy filtration systems that do not include an RO membrane and offer a lower cost. Hydro-Logic was also the first company in our industry to offer KDF-85 as a replacement/upgrade to the standard carbon filters in all the systems they offer. KDF-85 not only lasts twice as long as standard carbon, it also eliminates most of the chloramines present in municipal water. Unlike chlorine, chloramines remain in water for many months and cannot be removed by aeration or standard carbon filters.