My intex SWG (model 54601EG) is showing low salt level. My salt level is good so I am sure its the SWG. I was looking at them online and noticed the model 54605EG. It is setup different than my model. My pool is an 18'x54' intex metal frame. Anyone have experience with the newer model 54605EG or now the main differences between the two models? I do know the newer model says its good for pool up to 7000gal and intex only shows this unit on there web site. Thanks.