Water Chemistry

Hey all quick question. I am prepping my mixing station (very similar to what Drimo did) and although it is not stained I can still smell the soft drink syrup that was first in the barrel. Does this mean it still has the potential of releasing baddies into my reef tank?



PS i have already rinsed it a few times and also used some vinegar. I plan on getting a big jug of vinegar and rinsing it a few more times also. Thanks all