This is probably a simple question but I am still learning... I thought it was going to be easy getting sand for our filter but none nearby so I need to wait. Unfortunately I have the pool filled below the skimmer and would like to start circulating and adding chlorine. Can I just hook up the pump and then add the filter after I get the sand? If so, do I need to take water out of pool to below skimmer/return or can I temporarily 'plug' those points to plumb in the filter? Putting something in the bottom of the skimmer seems like it would work but how to plug the return?