I have just purchased 18x48 intex above ground pool, intex krystal clear saltwater system model cs8110 and intex krystal clear sand filter pump 14" model sf15110. do i still need to use the pump that came with the pool? if so which one hooks to the other. lastly i have in the past (without these extras) not had any time in pool due to not being able to keep water clear. with these extras should i use well water( which is very hard) or use culligan, i have access to both. I would love to be able to enjoy this year. please help!!!!!