I just watched the videos on deep cleaning and need advice on what the majority recommend. I’ve never knew about deep cleaning until today, so I have never deep cleaned and I have never changed the sand in it for approx 14 years(I didn’t even change it when I switched from baquacil to chlorine). I’ve noticed the past 4-6 years that it is taking many more days each year to get rid of the dead algea/cloudy water/etc. My sand filter is 500lbs. Since I have neglected the sand filter, should I opt for new sand or would deep cleaning still work. Also, with such a large filter, am I at higher risk of damaging those folding black thingies(yes, I just said thingies) with deep cleaning?