Saturated foam?
 

If the top of the flotation foam is still rock hard, is there still a chance of it being saturated underneath?

Take a core sample. (Use a knife and cut a plug all the way to the bottom). Inspect the plug for saturation as well as look at the bottom. Then use Elmers glue to glue the plug back in afterward. Nothing beats the good ol' Mark I eyeball when you have a question like this. :head:

Thank you Sir!! I was going to take the tank out. May still take it out and have it cleaned regardless. Really not trying to seperate the two halves to repour new foam. Thanks again for the advise. You guys rock!!