use 2 litre jug and fill half
Cream weighs less than the same volume of milk. If it is separated from the milk, cream floats on top because its specific gravity is less than that of milk.
The number of liters in ma small carton of milk depend on just how small the carton is. A single quart is approximately one liter, and a small, 1/2 quart carton, is about half a liter.
25 litres of milk bottles go into 5 bottles - It depends on the bottle size If a liter bottle (container as sold in food retailers) then 25 if a 2 liter then 12.5 bottles if a 4 liter 6.1 6 liter 4.1
Although it is almost impossible to separate Fats from Milk but you can minimize it. First boil the the milk at for 10-15 minutes, rest it to cool, Refrigerate the milk in a container of aluminium for 10-12 hours then get out the container, separate the thick layer of the Cream and then pass the remaining milk through a "Kitchen strainer" of small pores. This milk has least amount of fats.Otherwise Skimmed milk with less fats is available in the market.
Most containers are not filled to capacity. Head room is left to allow for expansion as the temperature varies. For instance, a 12 ounce cola can holds more than 12 ounces when filled to capacity. Some will recall the bulging tops on cola cans that have been frozen. So a milk container, while it contains a litre of milk and is called one litre has a capacity greater than one litre when completely filled.
The small pitcher used to place the milk or cream in for tea is commonly called a creamer.
A US quart is almost a liter (0.95 of a liter).
Well the big fat ones are a gallon. and the small skinny ones are a quart
I would start with a small bowl if milk, or put it in a water container that attaches to the cage. Or, get very small pellets of food and put it in milk.