A Liberal candidate says his party will not bring in the harmonized sales tax, even though Leader Robert Ghiz has said he might consider the tax if he could get a deal from the federal government.

"The Liberal Party will not implement the HST," said Gerard Greenan, candidate for Summerside-St. Eleanors.

Greenan made the assertion in an online debate on taxes and the economy Thursday. It was the fourth debate with representatives from all five parties hosted by CBC News.

But, at the first public leaders' debate on Sept. 8, Ghiz said he might consider the HST if he could get an acceptable offer of compensation from the federal government. He said Ottawa's offer to P.E.I. was unacceptable, although he had denied Progressive Conservative Leader Olive Crane's accusations of having secret HST negotiations with Ottawa.

The PC, NDP, Island Party and Green candidates participating in the online debate all said they oppose the tax.

"The main issue I see for Islanders is to make sure we retain our sovereignty — i.e. to refuse the HST," said Jane Dunphy, NDP candidate from Georgetown-St. Peters.

Darcie Lanthier, of Morell-Mermaid agreed.

"HST will hurt consumers and injured consumers are not good for business," said Lanthier.

The Island Party's Derek Peters, from the Tignish-Palmer Road district, said, "The thing about putting in the HST, once it's there, there's no way to get rid of it. The GST was supposed to be temporary. But it's 2011 and we're still paying GST."

The next online debate on rural issues will be held Sept. 27, with the sixth and final debate — open topic — on Sept. 29. Both events start at 6:30 p.m. and run for an hour.