Pacific Palisades, Calif. — A 2,000 foot-long ocean clean-up system left San Francisco last September with high expectations. The plan was to begin cleaning up the Great Pacific Garbage Patch, a giant floating mass twice the size of Texas.

But on Thursday, after months at sea, 24-year-old Dutch inventor Boyan Slat said there are some major setbacks. The pipe cracked, and a 60-foot section of it has detached.

Just before the launch, Slat took CBS News out on the water, and he had some reservations. At the time, the device floated freely with the currents, forming a "U" shape to corral the trash. A skirt about 10 feet deep was supposed to catch the plastic, but that also didn't go as planned.

Boyan Slat's ocean cleaning device. CBS News

"The system isn't able to retain the plastic well, so once it's caught we also sometimes see it floating out again," Slat said.

It picked up 4,500 pounds of trash, which is not nearly enough, according to some critics.

"You will have more plastics there next week and the week after, so the real answer is to not consume so many plastics," said Robert Reed, spokesman for Recology.

Slat said he thinks they're close to making his system work.

"I don't think we have much choice. This plastic doesn't go away by itself," he said.

Over the next two weeks, the massive system will be towed to Hawaii where the team will decide what design changes need to be made. The goal is to have it back out in the next few months for further testing.