Alex Gogolev, Ben Walker and Brandon Fushimi also scored for the Royals (11-10-0) and Brandon Magee chipped in with two assists.
Ty Mappin was a team-worst minus-3 for the Silvertips (7-14-2), who have lost eight of their last 10 games.
Victoria opened the scoring early in the first on an offensive face off when Gogolev batted a rebound out of the air and in behind Silvertips' goaltender Austin Lotz.
Everett had chances to score in the opening period, but missed two clear-cut breakaways against Polivka, including one that beat him but hit the post.
The Royals went ahead 2-0 in the second period when Crooks scored from the slot, taking a perfect pass from Magee from behind the net.
Walker made it 3-0 on a two-man advantage with a long, low wrist shot that eluded Lotz.
The Royals increased their lead to 4-0 in the third on a cycle play from behind the net that was finished off by Fushimi.
Crooks got his second of the night, and sixth in seven games, pulling a slick back-hand deke on a breakaway against goalie Daniel Cotton, who replaced Lotz after the fourth goal.
Lotz allowed four goals on 27 shots before getting pulled in the third period. Cotton played the final 14 minutes and stopped 8-of-9 shots in relief.
Victoria went 1-for-5 on the power play while Everett failed to score on three chances with the man advantage.
Silvertips' defenceman and 2012 second-overall NHL draft pick Ryan Murray left the game in the second period favouring his shoulder.