[Cruisingdad]

We just bought big blocks and wrapped it in newspaper. We tore holes in the newspaper to allow more cold air to come out. We always had problems with stuff near it freezing. I never perfected it.

How long will it last?? No way to tell as we do not know how much insulation you have in fridge, how often you open it, how tight it is, etc. All this stuff about CO2 seems way over blown to me. I have used it so many times I cannot say. And let's face it - no boat is tight. Crap, most of us can't even keep them from leaking water in - much less keep air in!!!

I say use the paper. I seriously doubt it will be as good as the product mentioned above - but it is a lot easier and cheaper and by tearing the holes in it, you can adjust the temp. Tightly wrapped, with little access to the fridge, we might get 5 -7 days out of it (of course, I have kids and it makes that really cool fog in water!!!!). We used top buy it at Walmart and then at some grocery stores... but many do not carry it anymore. After that, you are down to "water"-ice, which melts. Another way to minimize your cold air loss is to make sure the fridge is packed tightly (every air space). Some people even carry plastic bags of those foam peanuts and shove them in the empty spaces as they can. We used to cover the top of the fridge with a solar blanket (cheap) so that when opening you do not let out all the cold air.

Hope that helps.

- CD