Brown coconut is similar to water coco but has much more developed flesh inside that is perfect for making fresh homemade coconut milk or cream and has slightly salty water inside that is full of electrolytes & minerals that improve heart health & hydration.
In order to open brown coconuts you can use the back of a heavy knife & hit it along the equator to easily crack it open. If your after the water inside, the best way not to lose any it to punch a hole in one of the eyes. There is one out of the three that is softer and will cave in and let you pour out the water. You can then crack it open and harvest the fruit inside.