Originally Posted by charlieward
Thank you. aluminum tank idea has been discarded. Any suggestions as far as gallon size for fresh and grey? In the event we change our minds and go with black water tank, how many gallons? Thanks
Gray tank equal in size to the fresh tank. Black tank half the size of the fresh and gray tanks.
The reason for making the fresh and gray tanks equal size is so that you won't overfill your waste tanks before you run out of fresh water. When your fresh tank is empty, it's time to dump your gray tank, too.
As for size, you have THREE considerations:
1 - How much reserve weight capacity does your trailer have? When the fresh and gray (and black, if you don't have a composting toilet) tanks are all
full*, the trailer still has to be below its gross weight. Water weighs 8.34 pounds per gallon, so 30 gallons of water (for example) weighs 250 pounds, not counting the weight of the tank itself.
2 - How much space is available for the tanks? Obviously you can't put in bigger tanks than you have room for.
3 - How much water do you normally expect to use on a given trip? The ideal situation is to be able to carry all of the water you need for a trip, so you don't have to move the trailer just
to make a water run.
Taking the LEAST capacity from those three criteria, you should be able to figure out what size tanks will work best for you.
(*You have to assume weights based on every
tank being full at the same time, just in case circumstances force you to travel with full tanks all around. Overloading your axles and brakes just because your tanks can't be emptied before you hit the road is not worth the risk.)