How do you clean dirt off the bottom of the pool?

Use the type of vacuum that connects to a garden hose (got mine at Walmart for about $17). The bag provided isn't enough (pressure forces dirt though it and back into water). Make two more bags- large and medium like one that comes with vaccum out of interfacing material (I think it's called Pellon- looks like my cartridge filter is made of the same stuff). Overlap the bags on the vacuum smallest to largest. Air pockets will cause it to lose suction. Just squeeze bag when that happens (not in the pool water). I've had a cloudy (above ground) pool for months and this is the only thing that has worked. You won't believe what will be in that third bag. My filter never caught that stuff.

Your filter is damaged internally and needs repair if it is a DE filter. A sand filter will pass the finer stuff back to the pool. A hand full of DE added to the skimmer prior to vacing of pool will help some. Don't understand how you could tolerate a pool that was like the above for months. Sand filters should have the ability to switch to "vac to waste" mode. You are not going to get the mud off the bottom of the pool until you replace your damaged DE filter grids

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