Manning, who made it through two stages of Q-school to reach the finals, had five straight birdies in the middle of his round on the TPC Stadium Course, while Kanada started his round with six straight birdies on the Nicklaus Tournament Course.
Joey Lamielle, who also began his quest for a card in the first stage, had a 65 on the Nicklaus course.
The 108-hole tournament, one of the most grueling in golf, will end on Monday with the top 25 players and ties earning cards.
The biggest name atop the leaderboard was former PGA champion Mark Brooks, who is in Q-school for the first time in 21 years. Winless since his capturing the 96 PGA Championship at Valhalla, Brooks opened with a 66 on the Stadium Course.
The group at 67 included Jay Williamson, who reached the third round of the FedEx Cup playoffs but failed to keep his card. Joe Durant, whose four PGA Tour victories include the Bob Hope Chrysler Classic in the desert seven years ago, was among those at 68.
Among former PGA Tour winners who struggled was Jason Gore, who had two bogeys on his opening three holes and took a 7 on the par-3 eighth hole on his way to a 75.
Former U.S. Amateur champion Ricky Barnes already earned his card by finishing 25th on the Nationwide Tour money list, but he entered the final stage with hopes of improving his status for the 2009 season. He opened with a 72 and was tied for 104th in the 163-man field.