Pettit vs. Interlux

With equal amounts of slime—and no hard growth—these two super bottom paints are at a stand-off after eight months in the water.


Before we published the results of our annual bottom paint test last month, we’d set up a grudge match involving the two paints that fared best in our 2004 test—Interlux’s Micron 66 and Pettit’s Trinidad SR (see PS, Nov. 1, 2004). After eight months’ exposure in the drink, we’re ready to reveal the initial findings.

Readers will recall that both paints were applied to our 21-foot test boat in checkerboard fashion (yes, it’s a powerboat in this case). The starboard bow and port stern sections were painted with the Micron 66, while the port bow and starboard stern sections were coated with Trinidad SR.

Micron 66 is the rookie in this test, having only hit the market last year. It’s quite expensive at $194 per gallon. Interlux uses a patented resin—an SPC copolymer—that is released by a chemical reaction with salt water. This consistent release of biocides allows the paint to outperform a paint containing the outlawed TBT, according to Interlux. Micron 66 contains 40.41 percent copper and cannot be used in fresh water. Like many paints from Interlux, this one also contains “Biolux,” an anti-slime or soft growth additive.

Pettit’s Trinidad SR has been on the market for several years. A hard all-purpose paint, it’s quite different than Micron 66. Its copper content is significantly higher at 70 percent.

Both Trinidad SR and Micron 66 are “slime resistant.” In fact, that’s what the “SR” stands for. Trinidad SR sells for anywhere from $154 to $169 per gallon.

Eight months later, it appears that both paints did an excellent job preventing any hard growth from forming. However, both allowed their fair share of slimy soft growth. It’s evident that the starboard side of the boat collected more growth than the port side. The starboard bow (coated with Micron) and the starboard stern (coated with Trinidad) had noticeably patchy beards of slime. This slime could easily be removed by power washing or using a scrub brush. The growth on the starboard side is most likely a result of the boat’s docking: About two thirds of the time it was docked with the starboard side away from the dock and the port side directly against the dock.

We’ll wait another 6 to 8 months—or longer—to determine a winner for this test. For now, however, Trinidad SR is more appealing to us simply because it’s less expensive and slightly easier to apply.


• Interlux Yacht Finishes, 800/468-7589,
• Kop-Coat (Pettit), 800/221-4466,

Darrell Nicholson, editor of Practical Sailor, grew up boating on Miami’s Biscayne Bay on everything from prams to Morgan ketches. Two years out of Emory University, after a brief stint as a sportswriter, he set out from Miami aboard a 60-year-old wooden William Atkin ketch named Tosca. For 10 years, he and his girlfriend Theresa Gibbons explored the Caribbean, crossed the Pacific, and cruised Southeast Asia aboard Tosca, working along the way as journalists and documenting their adventures for various travel and sailing publications, including Cruising World, Sail, Sailing, Cruising Helmsman, and Sailing World. Upon his return to land life, Darrell became the associate editor, then senior editor at Cruising World magazine, where he worked for five years. Before taking on the editor’s position at Practical Sailor, Darrell was the editor of Offshore magazine, a boating-lifestyle magazine serving the New England area. Darrell has won multiple awards from Boating Writer’s International, including the Monk Farnham award for editorial excellence. He holds a U.S. Coast Guard 100-ton Master license and has worked as a harbor pilot and skippered a variety of commercial charter boats.


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