Once an outlying classroom for biology students at the College of Marin, the little-used Bolinas Marine Lab on Wharf Road will open its doors this weekend for a public openhouse.

The cleaned-up lab has also begun offering its facilities for rent.

Housed in an old US Coast Guard lifeguard station, the lab has been operated by the College of Marin since 1964 but in recent years has rarely been used by outside researchers despite its ideal location only 30 yards from the ocean.

Budget restrictions in the 1970s forced the college to let the lab fall into disuse until 1995, when faculty and students at the school's Life and Earth Sciences Department started turning it into working facility, said biology professor Joe Mueller.

"It's always been used, just not to its fullest extent," said Mueller. "It was used as a classroom rather than a living laboratory."

The laboratory is located in the boathouse section of the Coast Guard Station. Inside are 20 work stations, complete with microscopes and stereoscopes, where college students have examined all forms of underwater life.

Diagrams of sea creatures and maps of the coast decorate the walls, and the shelves are lined with jars of specimens collected over decades. Parasitic roundworms, short-spined sea shrimp, kelp crabs, herring, and smelt all float in formaldehyde.

But now there's signs of life inside the old building. A new 100-gallon tank houses sculpins (sea scorpions) and sea slugs, a species that, Mueller said, helps show changing climates.

Another tank contains monkey-face eels and sea urchins. A third houses two Green Crabs, an invading species that is spreading after infesting San Francisco Bay.

Mueller said two more 50-gallon tanks are to be installed soon, allowing researchers to bring even more live specimens to the lab for study.

"It's the optimum facility if you're going to be learning about this stuff," he said. "To be out in the field, and then come back to the lab to take a closer look really cements the process."

With the installation of the tanks, Mueller said, the lab is prepared to offer its facilities to anyone interested in research or learning more about ocean life. He said public schools, government agencies, and community colleges can now rent the station and hire students there to teach classes or help with studies.

To help spread the word about its availability, the Bolinas Marine Lab will hold the openhouse from 11 a.m. to 2 p.m. Saturday, Oct. 25. At that time, it will also dedicate a new dock paid for by Bolinas residents.

This week, Mueller was still working on the tanks in anticipation of the grand opening. "It would be nice to get a little abalone in there," he said. "I'd like to get a giant starfish, something a little more spectacular."