Normal De-Oxit (use the 100% solution) is mainly a contact cleaner and not enhancer so it should be completely wiped off with a microfiber cloth.
For contact enhancers I'd use Stabilant 22 gel concentrate (I've bought it for around $80 off of eBay, much better than the diluted stuff, the bottle is also large and can treat your entire house multiple times over), De-Oxit Gold 100% (significantly thicker and a better enhancer than the normal solutions, about $20-25 gets you a decent sized little glass container), Furutech Nano-Liquid (doesn't last as long as the previous two, but is a more powerful enhancer, costs nearly $200 though and the bottle is the smallest of the lot), or Mad Scientist Audio's Graphene Enhancer (most potent enhancer, only just started using it in the past couple of months, so not sure about lasting effects, seems to form a shell around the contacts though, $50 gets you a 5 oz. bottle which is a lot). I've seen and heard changes for the better with all of these. I know there are other enhancers, but I have not tried them. Usually with video at least everything looks better at first then settles a bit as the days go by. Audio I can't recall to the same extent as I last tweaked my video.
