Water Pump For 2nd Floor

We had an expansion tank added to the hot water heater and a sump pump that is water driven if the electricity goes out.
Water pump for 2nd floor. Water restrictors are designed to reduce the high constant water pressures of municipal water systems to conserve water. The farther pipes are from the main water line the less water pressure there is for fixtures such as sinks and showers. The water supply is only available for a limited period everyday and the goal is to achieve maximum water to the overhead tank. I keep accumulating a lot of water enough to fill a water basin every 2 days from washing stuff.
According to standard 5floors means approximately 15 mtr so we require 15 or more than 15 head of pump 25 hp pump having approx 3 to 24 mtr head. This leaves bathrooms on upper floors particularly at risk of low water pressure. Gallons per minute or gpm is the rate of water flow as measured in how many gallons of water a pump can process per minute pumps on the weaker end may have gpm ratings of 1 2 or so while pumps with gpm ratings of more than 4 are considered high volume water pumps. The hot water faucet to the bathtub used 1 2 times week developed slow flow down about 75 but cold faucet was fine.
Just 1 2nd floor faucet developed low pressure starting a couple years ago. How can i pump this unclean water from our 2nd floor to 1st floor down to our drainage. The water supply line provides water from a bigger 8inch main line but water pressure from it is not adequate to pump up water on top level. Water pressure only enough to supply water to first floor and that too.
I m thinking of using some kind of hose to transfer it. Two methods ensure there is enough water pressure on upper floors for properly running plumbing fixtures. Since your water heater is in the basement i m going to assume that the main water line enters through the basement as well. Water is going to enter your house at a certain amount of pressure.
As the water heads upstairs it loses pressure due to the vertical climb about 1 pound of pressure loss for every 2 3 feet that the water has to.