I would think that as to the "curing" issue that you could do so in another temporary tank or vat of saltwater so prevent it from affecting your display tank. As MKCindy stated a big issue is being able to keep it in place. I believe Ace had some difficulty with that issue on his new tank even though he worked very hard to make sure it was secure with eggcrate. I think if you spray the foam over a piece of rock, even a piece of limestone, they weight of the rock would help offset the bouancy of the foam.