Hmm! You are not isolating the water , you are adding more mass by adding the containment, mass of the container that is also being effected by gravity.The parameters were not changed. You mades some absurd claim along the lines that gravity is adding or subtracting energy to objects so to test that effect you must isolate other real sources of energy loss or gain.
It is quite simple though well beyond your abilities.
I have passed the idea on, I am not a scientist, I do not know all the in's and outs. I can say with an almost certainty that gravity attracts the energy of mass, whether the mass loses energy to gravity or not I could not say with a certainty, I have passed the idea on now so that is it for me with this one, bin it if you like no problem.