Two former guests at a downtown Los Angeles hotel where the decomposing body of a 21-year-old Canadian tourist was found in a water cistern have sued the hotel.

The lawsuit was filed Tuesday in Los Angeles Superior Court by Steven and Gloria Cott against the Cecil Hotel, one week after Elisa Lam was discovered at the bottom of a 4-foot-by-8-foot tank on the building's roof, The Associated Press reported.

The Cotts say that when they paid $150 for a two-night stay at the 15-story hotel they were promised running water safe for drinking and washing.

During their visit, Lam's body was found by a maintenance worker after hotel guests complained the building's water pressure was too low, police said.

The Vancouver, B.C., native had been last seen on Jan. 31 and is the subject of an LAPD homicide investigation, according to NBC Los Angeles. An autopsy was performed, but the official cause of death has not been disclosed.

Los Angeles health officials announced last week that water from the hotel's tanks does not contain harmful bacteria.

Ho / AFP - Getty Images

This undated image released by the Los Angeles Police Department shows Elisa Lam of Vancouver, Canada.

Samples taken from inside the water cistern and within the building all tested negative for fecal coliforms and total coliforms, according to Angelo Bellomo, director of environmental health for the Los Angeles County Department of Public Health.

"It's likely there was sufficient chlorine in the tank to destroy any bacteria that might have otherwise been present," Bellomo said.

A do-not-drink order is still in place in the building, according to NBC Los Angeles.

Representatives for the Cecil Hotel did not return calls for comment.

Related: No harmful bacteria in hotel water tank where dead tourist was found