The hydrometer is a simple tool to measure the salt content of the water in your aquarium, or the mixture that you make to add to the aquarium.
(The hydrometer; is; a simple tool to measure the salt content of the water in your aquarium, or the mixture) (you; make; ) Context(you make,List([111, 119))):(the mixture; to add; to the aquarium)
you make,List([111, 119))
The hydrometer you the mixture
is make to add
a simple tool to measure the salt content of the water in your aquarium, or the mixture
to the aquarium