Clothes? What clothes? Ha ha. What we do on our tiny trimaran
Wash in fresh. Minimal water
. Minimal soap. Agitate and scrub apenty. Rinse in salt water
till all the soap is gone. Rinse in fresh. Squeezing most of the water
out between steps is also important.
We have a water tank holds 40 gal max. Another 15 in jugs. We crossed from panama
4000 miles nonstop. 25 days. That was our longest passage
to date. We washed clothes twice after rain showers. I guess what i am saying is you dont really need thousands of heavy gallons of water. Just be frugal and concious of water usage. If you dont have it to spare, dont wash the clothes.