i have a pool that is covered a large percentage of the time and i am constantly battlling the dreaded bacteria. i brush daily along with slamming and algaecide 60. the water has a slightly turbid appearance i cannot seem to get rid of this year. i also have added well water through a filter and have had some staining. i have added a metal chelator which helps but i suspect the iron level is causing the faint brownish tint. the ph is holding in the 7.2 to 7.6 range. my cya is down to 30 to 40. the alkalinity is down to 90.my free cl is holding around 1 to 2,but my total is 3 to 4. i used to use cl tablets and non cl shock almost exclusively until my cya got to 120 to 150 or higher so i been adding liquid bleach and shut the chlorinator down. it is a vinyl pool which is winterized each year. i have used some organic products such as pool perfect and seakleer for water clarity and phosphate removal that have worked in the past but now i cant seem to eliminate the faint haze. my filter sand is original 2007. should i change sand? i have an oversized filter which does not register much pressure change but seems to remove the whiter turbidity which i see in the sight glass when i backwash but not as much as in the past. should i try adding a filter aid? i have used a filter cleaner recently when backwashing which helped last season but not this year. i have brushed daily especially in dark areas and kept the white slime in those areas as well as brushing all surfaces. i use the pentair 78dpd+ test kit.