The NRL uses a two referee system while Super League has just one.
“I’ve always wanted to come to Super League,” the 28-year old told Love Rugby League.
“I watched Super League growing up. They always had a physical game, so I wanted to come here to try it out.
“I’m expecting it to be a little bit slower.
“I think there’ll be a lot more wrestle here, like back in the old days in the NRL.”
Manu arrives after several successful years and grand finals with the Melbourne Storm. The Kiwi international has spent the past three seasons with the Penrith Panthers.
Manu has played 14 times for New Zealand and also made six appearances for Tonga, including at the 2013 World Cup.
He is not taking success for granted, though, despite the standard of player available to FC coach Lee Radford.
“I think we can go a long way this year,” he said.
“But a good team on paper doesn’t mean anything.
“Hopefully we can perform week-in and week-out.”