Shallow well pumps are found in applications of 25′ or less. This style of well pump is not submersible and is placed outside the well in a well housing.
If you have really low water pressure coming from the city supply or have low pressure because you are on a well installing a pressure booster pump could be the solution you have been looking for.
A Sludge Pump is a type of centrifugal pump, lobe pump or peristaltic hose pump in physics principle that increases the pressure of liquid and solid particle mixture (aka slurry).