DIY steps for installing a Grundfos Model SBA 3-45 A, submersible, on-demand pump in a 2500 gallon water storage tank. Don't want to have to climb in your water storage tank when it's full of water when the pump needs to be serviced? Watch this helpful video to see one way that the pump may be installed that will allow you to pull the pump from the water tank without getting in the tank.