Help! soap - cleaning tank

[RedFish]

A friend has given me a large goldfish bowl, that I may be able to use to temporarily house my new betta.  My problem is that she kept fancy little soaps in it.  I have rinsed it a zillion times with extremely hot water and rubbed the insides with a cloth too.  I also rinsed it with vinegar (not sure why, it just sounded like something I should do).
How can I possibly be sure that I have cleaned it enough to put a fish in it?  Any suggestions?
Thanks,
Lynn.

[ambushman2j]

to my knowledge I don't think you can be sure, you just have to trust yourself that you did a good job

[RedFish]

You are right, and after multiple cleanings I am quite confident that it is safe.

[dpatte]

I think the best way to remove soap is to dry with absorbent paper - and I'd wash it 20 times!

[tigerize]

If you can still smell any trace of the soap then it is not good. If you can't then it should be ok.

[RedFish]

I washed it more than 20 times,  :shock: , scrubbed it with baking soda and rinsed it a dozen times more.  I think it is the cleanest thing in my house.  
After all that, Big Als didn't get in the mustard fan tails that they ordered.  However I was READY in case they did.  :wink:
In another week or so, the big tank will be cycled, the betta in my qt will move in , and I'll have the qt tank available again, gonna get me some more fishies....