Build a Washing Machine Greywater Surge Tank
...u want to be able to hold the water in the tank temporarily. Remember that greywater quickly turns into black water if allowed to sit around for more than 24 hours, so use this water quickly. 4. Direct your washing machine’s drain hose into the tank. The hose must first go above the top of the machine before going down into the tank in order to prevent the machine from draining accidentally. Also, don’t make this connection airtight–the washing ma...