I know you said you mixed it well, but you need to make sure you don't leave any of the resin still stuck to the bottom of the jug. This is your hardener. If you can get some kind of mixing paddle in there you can get it mixed better. Are your baits sticky at all? Like Denny said, the HD additive will toughen your baits considerably. For saltwatet use I would think hard formula would be better.