Weight of 1 US Gallon of water = approx. 8.35 lb (about 3.79 kg)
Weight of 1 Imperial gallon (i.e. UK measure) of water weighs 10 pounds by definition, at a specified temperature and pressure. (4.536 kg)
One CC of pure water weighs one gram and therefore one liter (1,000 CC) weighs 1 kg. At 4 degrees Centigrade, which is water's maximum density, one liter, therefore, weighs 2.205 lbs. Interestingly, that non-linearity of water's mass vs temperature is one of the reasons that there is life on earth. Consider that ice is colder than 4 C and has less density the warmer water..At 4 degrees the warmer water sinks to the lake's bottom. Therefore ice floats and the colder the ice gets, the density goes lower and displaces less water. If this were not true and the ice sank, there would be no liquid water in the winter for your enemas.
Now, the matter of the electronic scales. I have two of them and it seems they never agree because the number you get is only as good as the last standard calibration. A second factor depends on how you stand on them. These errors can vary widely. The scales are fun to play with but as measurements of water you have on board, an accurate measurement may be nearly impossible. Another variable not mentioned before, is the amount of waste material that gets dumped into the toilet upon expulsion or urination. I guess that means, "Don't count your hatches before they're chickens!"
What does all of this mean? Suzie said here, " All you're doing is giving yourself extra work in cleaning out a dirty bucket after your enema." It can be fun making these calculations and trying to figure what you have on board but no matter what you do, it's all about enjoying your enema and feeling good about yourself. No matter what you do with all of the record keeping and calculations and exercises, IT ALL COMES OUT IN THE END!
It's an enema, not a race! Enjoy it!
An enema a day keeps the doctor away!
Bill