Australia's Science Forum

We have never had much luck doing the Diet coke and Menthos. Do you use the menthos straight from the pack or do you crush them a little to get more surface area. I read somewhere that the Australian menthos had a smoother surface so didn't work as well.

Using my little contraption I made last week I got the fountain as high as a house roof in my trial before doing it for the kids. But when I did it for the kids the mentos got stuck in the tube and blocked it meaning a fine spray came out instead :( most disappointing for me but still exciting for the kids (they didn't know what was supposed to happen). I am going to do it again tomorrow without my contraption (which I made intending to get a higher fountain than you'd get just through the opening of the bottle) and also do the elephant's toothpaste. Hopefully I'll get some photos and post them here for you

Another tip for the heated up diet coke is to open the lid VERY SLOWLY!