Not many sparks flew during a taping of the latest debate between the four candidates vying to become the next leader of B.C.'s New Democrats.

John Horgan, Dana Larsen, Adrian Dix and Mike Farnworth covered various issues during the hour-long taping in Vancouver, to be broadcast on Sunday afternoon on Shaw TV.

The contenders mostly agreed to vote against the harmonized sales tax in the upcoming referendum, increase spending on education and health care, and roll back corporate tax cuts, gambling and Medicare premiums.

They also proposed to review fracking, a process in which water is pumped into the ground to extract natural gas, as well as tolls on the Golden Ears and soon-to-be twinned Port Mann bridges.

The candidates took questions from media panelists. They also had a chance to ask each other questions, which they mostly used to showcase one another and blast the B.C. Liberals, rather than distinguish themselves from each other.

Larsen, a marijuana activist, lobbed one of his questions at Horgan, the party's energy critic about BC Hydro's controversial contracts with independent power producers.

Horgan returned the favour in one of his questions, and let Larsen promote his plan to regulate and tax marijuana.

Farnworth took a shot at Dix's ability to unite the party, highlighting his own endorsements from either side of the rift that divided members over former chief Carole James' leadership.

Dix listed his own endorsements, including one from former leader Joy McPhail, and promised to bring the party together.

"If I'm elected, I'll work with every member of caucus and every leadership campaign," Dix said. "And if I'm not elected -- and everybody who knows me knows this -- I will give everything I can to make whoever wins the premier of British Columbia."

On his turn, Dix tried to poke holes in Farnworth's plan for an education commission. He said he wouldn't delay on important problems like province-wide tests to determine the level of students' skills, something he said Farnworth's commission would.

Farnworth said Dix misunderstood, as his commission would take a long-term look at the system. If elected, the Port Coquitlam representative said he would address underfunding, province-wide tests and class sizes right away.

Horgan trotted out the need for a provincial police force after Farnworth asked him about contracts with the RCMP. Horgan also emphasized his plan to hold a fair tax commission to help the public better understand where the government gets its revenue.

New Democrats will mark their ballots for a new leader on April 17.