No. It does not remove hardness, so the water still tests hard and will not feel slippery. It keeps the hardness from sticking: Aidan's words are that it converts it "to a microscopic crystal, so it can't attach itself to the plumbing and the water-using appliances." If you want soft water, choose a salt softener.

For most homes, Aidan recommends the softener: it removes the hardness and costs less to run. For this size, the Whole house water filter and softener (1.5 carbon + 48,000 grain softener) ($3,195). Choose this salt-free pair when you cannot run a drain or outlet to the spot, do not want to carry salt, are on a diet that limits sodium or potassium, or only need to stop scale. Not sure? Text Aidan at 443-277-2204.

Aidan sizes it for up to about 25 grains per gallon. Watch Water rates its media higher, but above 25 grains Aidan recommends a salt softener. Your water report may list hardness in mg/L; divide by 17.1 to get grains per gallon.

City water carries chlorine or chloramine. The carbon tank removes them, with the taste and smell, and protects the conditioner: Watch Water limits free chlorine reaching its media to 3 ppm, and SP3 also soaks up metals that would shorten its life.

Both. Centaur is a catalytic carbon that Calgon Carbon makes to break down chloramine faster than standard activated carbon. This 1.5 cu ft tank gives chloramine Calgon's full contact time at up to 3.7 GPM of steady use, about a shower and a bathroom sink at once, and chlorine at up to 5.6 GPM. Above that the water keeps flowing, with a little less time in the carbon.

Aidan's answer on these Vortech tanks: "we don't really get any complaints about flow or pressure drop." Both tanks use 1 inch Clack heads and Vortech tanks with no gravel bed. Aidan puts the flow through a single 2.5 cubic foot tank at about 17 GPM, and on a two-tank setup with a 1.5 cubic foot carbon tank he says two showers run at once with barely a drop in pressure. The 3.7 GPM on this page is not a flow limit: it is how fast water can move and still get Calgon's full chloramine contact time. Above it, the water keeps flowing. If your home runs more than that for long stretches, the next size up gives the water more time in the carbon. Not sure? Text Aidan at 443-277-2204.

Carbon: about 4 to 5 years for three or four people, longer for two (Aidan). A carbon refill is 1.5 cubic feet of Centaur: 1 x 1 cu ft bag and 1 x 1/2 cu ft bag. The 1 cubic foot bag is $295 today, so $295 plus the 1/2 bag, which Aidan prices by text. Filtersorb SP3: Aidan plans on about 3 years; Watch Water rates it 5 to 7. Aidan quotes about $1,200 to $1,500 for the 14 liters in the 2.5 cu ft; for the 9 liters here, text him for today's price.

We recommend one. Each tank is an inlet and an outlet with no drain line and no electricity, about two to four hours of a plumber's time for the pair, and Aidan supports your plumber by phone at 800-460-5810. If you'd rather do it yourself, you can; text Aidan at 443-277-2204 with any questions.

No. Both tanks ship empty. The carbon and the Filtersorb SP3 ship separately and are poured in through the included funnel at install. A filled tank is too heavy to ship safely and could be damaged in freight.

Aidan recommends a regular salt softener ahead of a tankless heater. A conditioner leaves the hardness in the water, and a softener removes it.

Activated carbon reduces some PFAS, but this system is not certified for PFAS removal and we do not claim a percentage. It does not remove lead or fluoride; those need different filtration, usually at the kitchen sink. A city water test tells you whether you have them.

Yes, if a well test shows the water suits it. Watch Water, which makes Filtersorb SP3, lists a pH of 6.5 to 9.5, iron no higher than 0.5 ppm, manganese no higher than 0.05 ppm, and no hydrogen sulfide (the rotten egg smell) or oil. It also says the water must be microbiologically safe or disinfected, which on a well usually means a UV light. Aidan is stricter on iron: he will not put a salt-free conditioner on water with iron. Hardness still has to be 25 grains or less.

On a well there is no chlorine for the carbon tank to take out; it still reduces taste, odor and many VOCs. If your well has none of those, ask Aidan whether the Salt-Free Water Conditioner on its own ($2,495) is all you need.

If the test shows iron, sulfur, acidity or bacteria, those are treated first, and after that Aidan usually recommends a salt softener. Text your well test to Aidan at 443-277-2204 and he will tell you what fits.

Filtersorb SP3 is certified by IAPMO R&T to NSF/ANSI/CAN 61 and 372, which cover materials safety in drinking water. Those standards do not test scale reduction, and we do not claim a scale reduction percentage.