I have the yellow top optima and I have been building my car for 3 years and drive very little and just keep charge on it every once in a while when I run it down from playing the radio, It still works great and in 110 degree summers.

 

You had me worried for a minute. when mine blew I got acid on me as well so I had to qwickly take a jump in the pool....AAAHHHH!!!

 

could this happen to the sealed batteries too? I just bought a kirkland sealed battery, I dont think i can fill up the water on it.

 

It can happen to ANY lead acid battery, sealed or not. The sealed ones have a designed relief port. This should never happen to the normal batteries in a 996 unless the vent tube is clogged or pinched, which is probably the reason his Interstate blew up. The vent is there to vent the hyddogen pressure that can build up. Don't assume it was a defective battery, just because the new one works fine. The old one was fine right until it blew up. Take some compressed air and blow out the vent tube and verify it is clear. Check water every few months.