The Umbrella / Mushroom Jet produces a sheet of transparent water thanks to a fully laminar flow of water at the outlet. The name comes from the bell-shaped sheet of water it produces. Crystalline and laminar jet performed by the Mushroom Jet. It has little wind resistance, although this also depends on the thickness of the water film. Due to its operating speed, noise level is very low, which makes it particularly suitable for indoor fountains. As it does not depend on the level of water in the fountain pond, it is advisable to set to a height at which the film does not break when it falls. The Bell nozzle, sometimes called a Mushroom nozzle due to its rounded shape, creates a sheer bell of water. The nozzle can be adjusted by tightening or loosening the top brass plate which allows for fine tuning of the bell size. The bell shaped water cascade almost appears like a half bubble on the pond. It leaves a delicate sound and is ideal for formal lily ponds or any backyard pond. Can also be used in formal commercial basins. The overall diameter of your Bell spray pattern a will depend on the pump flow and the size of the nozzle chosen. Ensure that the hose or PVC tubing that connects your pump to the nozzle is a sufficient diameter. Always try to use a pipe with the same diameter as the nozzle to minimize loss of flow from pipe friction.