I'm sorry . somehow I missed this reply.Please tell me the gravitational force that is able to hold trillions of gallons of water to a spinning planet but cannot hold down a helium or hydrogen balloon at the same time. Surely you do not think the calculation (or measurement of gravity's force )is the same for both - which is exemplified in my previous statement that gravity is a very convenient and flexible force - capable of being extremely strong or extremely weak when it suits either argument.
You are confusing Buoyancy with Gravity, the two can co exist, and work together, or fight each other.
Yes, the same calculations are applied to both water and helium when predicting the effect of gravity, part of the calculation includes the mass of the substance, hence gravity has a greater effect on substance of greater mass.