Big Boy Pantsâ„¢ Plain Janeâ„¢ Coconut Fiber is the basic foundation for your growing program. Itâ€™s a Plain Janeâ„¢ mix that contains a proprietary blend of low salt fiber and pith for superior aeration and optimal water retention. Pure and simple! If youâ€™ve been looking for a soilless media that you can use with a customized feeding program, look no further. Big Boy Pantsâ„¢ Plain Janeâ„¢ Coconut Fiber is the ideal substrate for your hydroponic growing system.