I'd like to go for solo day paddles, but would prefer having some weight in my canoe for a more solid response on the water. Having no ballast is like paddling a twitchy leaf. Am I wrong? Right? What is most sensible as ballast? Pack of rocks? Jug of water? And how much weight is enough to carry? I paddle from a kneeling thwart in a tandem. Thanks for any advice. I'm a tandem paddler intrigued by this solo stuff.