Closed my pool in November after reaching 55 degrees. Drained 1 inch below returns/skimmer and drained the pipes with shop vac. Pump,filter,drained of course. I have drained approx. 4inches rain out of the pool since closing and have gained it back since this area is getting record rain fall this year (E.TN.) I am approx. 6 inches away from being full for opening. I have all returns plugged and the "gizmo" in the skmmer. Last year I drained too much and ended up having to pay for water that rain would have replaced. Will there be any harm in letting the pool start filling up for opening?? I plan on opening the first of March or when the temp. approaches 60 degrees. The "late closing,, early opening" sure helped in the algae batttle!! Thanks to TFP for all the info, without it I would still be paying for everything and not known what little I know of chemical balances. Besides, doing it yourself is part of the enjoyment of having a pool!