Because of its naturally aerated structure, coco coir is almost impossible to over water. In fact, coco coir can hold up to 8x its weight in water, and rather than over-saturate, will simply reject what it can't absorb comfortably. If you provide too much moisture to peat bases, for example, you run the risk of water logging. Not so with coco coir.
YOU MAY THINK YOU'RE GETTING ALL YOU CAN OUT OF YOUR WALL FAN SYSTEM, BUT... IF YOU AREN'T USING THIS, YOU HAVEN'T SEEN THE POWER OF A PREMIUM WALL FAN SYSTEM, OFFERING SUPERIOR CONTROL, UNPARALLELED