How much water to add to rice cooker when cooking brown rice? I usually use 1.5 cups of water for every cup of 'white basmati' rice.

Today I used 4 cups of water for 1 cup of 'brown basmati' rice and it came out a bit watery.  however i did add more of the water after one round of cooking so maybe that had something to do with the visible water in the rice cooker?
A little experimentation with each machine is in order as boiling time and amount of steam lost varies.

A good starting point for short-grain brown rice is to cover by inch.
2 inches if rice is to be rinsed and further steamed.