Jason Prior and Terry Dodd scored all five as the Rocks put their Sittingbourne stalemate behind them and moved up to second in the Ryman one south table.
Prior scored a hat-trick inside the first 55 minutes and Dodd added another two in the final 20 minutes as the Rocks found it ultimately easy overcoming the challenge of the lively but limited bottom-of-the-table side.
The three points put them back above Worthing in the top three and four clear of Whitehawk, the title favourites, who lost at Godalming, and puts them in good heart for Saturday’s FA Cup visit of Sittingbourne.
The Rocks were on the front foot from the first whistle and only two minutes had passed when Dodd glanced a near-post header just over the bar after Ben Johnson got away down the left.
Prior’s low cross on four minutes was just behind Dodd, who had two fierce shots on goal as the Rocks set up camp in the Crawley Down half.
A goal was almost inevitable and it came in the 11th minute when Prior sidefooted in a volley from another Johnson cross.
It was almost 2-0 two minutes later as Crawley gave the ball away and Dodd was sent through but his shot from an acute angle fizzed across the face of goal.
Crawley Down were struggling to keep the ball for long and their best chances came through hesitancy among the Rocks’ back-line rather than through anything they created themselves.
James Fraser’s rising shot from the edge of the box after Dodd’s chase down the left and clever pass inside was only inches over keeper Mark Zawadski’s bar.
Prior almost robbed Zawadski in the area on 26 minutes but the keeper scrambled it clear.
A lovely cross-field moved ended with Johnson’s inswinging cross being backheeled towards the bottom corner by Dodd, but the keeper got down to it in the nick of time.
Crawley gave the Rocks the scare when Ashley Rees hammered a volley that beat Craig Stoner and skimmed off the top of the crossbar. Rees went close again but Stoner was equal to his lobbed effort on 32 minutes.
Crawley were improving as the game went on and were starting to unsettle a Rocks side who were finding it hard to build on their early goal.
Rees nodded a tricky inswinging free-kick wide of Stoner’s near post after beating his marker to the ball.
But Prior doubled his and the Rocks’ tally on 39 minutes when he ran on to a Kane Wills through-ball, dribbled past two defenders and scored easily past the outcoming Zawadski.
The first booking of the night was shown to Jon Marzetti after he hauled down his man as Crawley tried a quick break from inside their own half.
Dodd almost bustled through for a third Rocks goal before the break as Crawley wobbled.
Any thoughts that the Rocks could coast through the second half were blown away in the 52nd minute when Connor Saunders nipped in at the near post to nod a corner past an unprotected Stoner.
But home nerves were settled three minutes later when Prior completed his hat-trick, sidefooting home when Fraser squared to him after chasing a deflected through-pass into the area and catching the keeper in two minds.
Crawley right-back Charlie Dodds went into the book for hacking down Johnson as he was in full flight down the left, with the Rocks now appearing to have been settled down by that third goal.
Crawley reminded the Rocks they still had a game on their hands with a counter-attack that ended with a weak shot by Dodds that Stoner gathered comfortably.
Fraser almost poked in a fourth at the near post but the keeper got down at his feet to deny him twice, and then Prior sent a shot out for a throw-in when well placed.
Lewis Ide replaced Fraser after 64 minutes before Prior and Dodd charged away down the right in a move that ended with Prior’s lob finding Dodd in the centre, only for his shot to go well wide.
A minute later, though, he made up for it as the 336-strong crowd got the fourth Rocks they wanted. Dodd was the scorer - a reward for a hard-working night - as he received a ball into his feet, turned, beat his defender and shot past Zawadski at the second attempt.
Darryl Wollers and Jack Blatchford came on for Prior and Dan Beck with the points safely in the bag, and both sides continued to get forward in the search for more goals, with Marzetti seeing plenty of the ball down the right.
Crawley caused a couple of alarms in the Rocks’ back-line but the hosts looked the more likely to score and they did put the seal on the win with a fifth, Dodd heading Ide’s cross from the right beyond Zawadski’s dive just before he was named man of the match.
Rocks: Stoner, Crane, Whitehead, Fraser, Marzetti, Bond, Beck, Wills, Prior, Dodd, Johnson. Subs: Ide, Wollers, Blatchford, Nightingale.
Crawley Down: Zawadski, Dodds, O’Neil, Jones, Saunders, Nyang, Graham, Cane Rees, Bradley, Dunn. Subs: Belli, Harding, Johnson, Tobin, Fox.
Ref: M Taylor (Southampton)