I plan on using cider vinegar to clean the inside of the tank and it should do a really good job since there is only some surface rust/varnish. I recently sprayed water in it and cant get all of it out. Idk how the baffle is set up on the inside of it but wth i should be able to drain all the fluid out with no problems. So does anyone has any ideas on how to get it? Have you cleaned a tank before and what did you use? If you used vinegar how well did it work?