Every couple of weeks i find my coolant level at the minimum so i top it off to max with some water. I know i should use antifreeze but what i thought what happened is that water just evaporated and the mix was just a little more concentrated with the antifreeze? Like if you boil down salt water, the salt stays but water evaportates. So i added water to make up the difference, but every 4-5 weeks its back at minimum. Is this normal? I am sure there are no leaks.

 

I don't know for sure, but I've only needed to top off once in over two years.

 

Look at the reservoir again.. there is a line high up that is just a line, the max line is low. I bet you are overfilling it and it just pushes the extra out the overflow when hot.

 

It HAS to be going somewhere. If you can't see any external leaks, it must be an internal leak, such as a blown head gasket. This is something the dealer should look into and fix for you. I wouldn't wait until the engine overheats. Get it fixed as soon as possible.