I have only used the blue or others like it in 5 or 6 gal jugs a few times, but if you tighten them when hot (soon after filling with 185-190F syrup) then tighten and turn them on their side for at least 30 seconds they will do well, as long as the jug was clean to start. I never even used a wrench to tighten, but often needed one to loosen the caps when opening.