Thank you sir, i will have to view this
This vid shows a couple of ways you can attempt it, either by using a dent removal tool or filling the dent and repainting it. I'd probs look at the first option. (not my video BTW)
i am betting mine is twin skinned. (dont know what that means but its a fairly thick tank). Plus it's like a palm sized dentDepends on your tank construction, a old trick was to put a length of chain inside and use it to gently tap the dint out by shaking it around. Problem is many modern tanks are twin skinned.