"It was hard to get a good one but I just lucked into the right waves really.
"It's definitely been a while since I have been in a surfing event but it is good to be back out here and making the most of it."
Moretti, 19, who is cutting his teeth as a builder in Auckland, said he would compete in the next Billabong Grom Series instalment at Piha, however he hopes to go a few results further.
"I've been surfing all summer at Muriwai so, luckily, I've had heaps of time in the water."
In addition to Moretti's result, Whangarei surfer Grace Pevats was second in the under-14 girls final at Whangamata.
Pevats posted a total heat score of 2.8 in her final but succumbed to Gisborne's Kai Woolf.