Mr Williams said all the proceeds from the event went back into community projects, including the installation of recliners in Northland hospitals.
A spokesman for Auckland company Boom Boom Fireworks, who put on the show, said the selection of fireworks included crossettes, a comet which splits into two at the highest point of its launch; dragon eggs, a gold or silver breaking effect that ends in crackles or strobes; waterfalls, a cascade of silver sparks; and comets, a star or other projectile which leaves a glittering trail behind it.
The spokesman said the most spectacular fireworks were the fast-paced multi-shot cakes - 300 individual shots in eight seconds - and the brocade waterfall star shells, which are fired about 130m high and then burst open into a cascading waterfall of sparkling stars.
Meanwhile, it was a "steady" weekend for the Fire Service as Northlanders took to backyards, beaches and parks for some DIY pyrotechnics.
Fire Service communicator Carren Larking said call volumes were comparable to a stormy weekend, "and most of the vegetation fires called in weren't to do with fireworks".
"Across the whole of New Zealand [on Saturday] there were only 67 fireworks-related calls. Not a huge amount, so maybe that education is getting through," Ms Larking said.
The major fire over the weekend was a 200sq m scrub blaze at the north end of Matapouri beach, called in about 9pm on Saturday.
But Ngunguru chief fire officer Mike Burr said this was not confirmed as fireworks-related.
Two Ngunguru appliances were assisted by the Rural Fire Service, with it taking about two hours to bring the blaze under control.
"When I arrived ... one man was doing his best to beat it out with a wet t-shirt," Mr Burr said. The man was moved away from the blaze.
Crews went back yesterday morning to dampen down.
"It was good team effort and some handy water there which helps," Mr Burr said.