Pool Paver sealant questions

I had pavers installed in my pool about two years ago and never had them sealed. Last spring I added sand between the cracks. In the area that gets the most wet, it seemed the sand and dirt below create a muddy musty result. Today I pressure washed them and removed most of the musty sand. I am going to reapply the sand and seal them. The sand I am using is the same sand for a kids sand box. The contractor that installed the pool told me to do this. 1. When I reapply the sand, how close to the top of the paver should it come. 2. After I apply the sand, should I lightly pressure wash and allow everything to dry before applying the sealant. 3. Is there any special type of sealant that I should use and where in North Florida can I find this. Thanks for your help.