Well said ms f. Yes do test it, for reasons above and also to check your hot water tank can manage it! I had a relatively fast birth and we still got it up in time, just get your other half to start inflating it as soon as you think you are definitely in labour. One tip I was given was to fill the cold water first and then you only have to put the hot in once you are ready to get in. My tip would be to have your kit ready and accessiblenieinplain view, eg your towels, buckets, dressing gown etc as you don't want anyone asking you where stuff is when you are concentrating.