Hi Ironskull,
You can drain the water by the exhaust fitting and tube from the beside hole of the reservoir. Here are the products links.
https://shop.bitspower.com/index.php?route=product/product&product_id=6991
https://shop.bitspower.com/index.php?route=product/product&product_id=2246&search=C02&page=2
https://shop.bitspower.com/index.php?route=product/product&product_id=2898&search=3858
