heya- i wanted to ask a question about useing the caulk on the great stuff- ive come across an issue with makeing my own clay and it the lack of staying power on the foam, as well as temp changes cause warping that cause cracks- its frustrateing! i wanted to ask how well the caulk works on the foam, adhearing and so on, because this isnt working so well for me ( it looked great, was non toxic, but it keeps cracking ~whimper~) i just like your idea and hope it holds my tank setup together 
