Is it good that it does not have flow switch? 12,000 gal. I should buy 25,000 - 30,000 gallon SWG? Do I want the SWG to have self cleaning cell mode? Also, is my 16" sand filter big enough to do a good job for pool size or should I upgrade to a bigger one? Mine needs about $110.00 of repair work anyway, should I upgrade to bigger tank and use same 1hp power flo pump setup? Thanks and please give me all the help and info you can. Just got pool and am kind of new to pool maintinance.Let all the good if on alternate chemicals. Kind of debating on SWG. Will it save my money in the long run.