Based on the aggregated intelligence of 170,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, water and air purifying systems specialist Calgon Carbon (NYSE: CCC) has earned a respected four-star ranking.

With that in mind, let's take a closer look at Calgon's business and see what CAPS investors are saying about the stock right now.

Calgon facts

Headquarters (Founded) Pittsburgh (1942)
Market Cap $857.7 million
Industry Commodity chemicals
Trailing-12-Month Revenue $444.7 million
Management

CEO John Stanik (since February 2003)

CFO Stevan Schott (since July 2010)

Return on Equity (Average, Past 3 Years) 12.8%
Cash/Debt $45.0 million / $23.6 million
Competitors

3M (NYSE: MMM)

General Electric (NYSE: GE)

Siemens (NYSE: SI)

Donaldson Company (NYSE: DCI)

Sources: Capital IQ (a division of Standard & Poor's) and Motley Fool CAPS.

On CAPS, 94% of the 308 members who have rated Calgon believe the stock will outperform the S&P 500 going forward. These bulls include CAPS member Reddrummer and All-Star Geofiz, who is ranked in the top 10% of our community.

This past summer, Reddrummer summed up the Calgon bull case: "Boring but profitable small company with good growth prospects. ... [P]eople always need clean water and air. As regulation on pollutions increase, so should [Calgon's] profits."

Calgon remains one of our community's favorite plays on the distressing trends in water availability and drinkability around the world. With a market cap of less than a billion, Calgon's three-year compound revenue growth (10.4%) tops that of much larger rivals like Siemens (5.6%), GE (-1.3%), 3M (2.3%), and Donaldson (-0.7%). Calgon also sports a lower debt/equity ratio than each of those same rivals, so it seems like a relatively safe bet, as well.

CAPS All-Star Geofiz elaborates:

A leader in a field that is destined to expand in the coming years. Revenues and [free cash flow] have increased steadily over the past couple of years, while margins have been squeezed just a bit. Beautiful balance sheet, with low, well-covered debt. [Calgon], along with [Flowserve (NYSE: FLS)] and a small, speculative investment in [Tri-Tech Holding], comprise my 'water portfolio.'

What do you think about Calgon, or any other stock for that matter? If you want to retire rich, you need to put together the best portfolio you can. Owning exceptional stocks is a surefire way to secure your financial future, and on Motley Fool CAPS, thousands of investors are working every day to find them. CAPS is 100% free, so get started!

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. 3M is a Motley Fool Inside Value selection. Try any of our Foolish newsletter services free for 30 days.

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