DE in the pool

[crkva]

Hi, I am new pool owner and trying to use BBB method to open my pool. After SLAM my pool had a great sparkling water, but suddenly I noticed that is getting murky and saw dirt coming out of return lines. Replaced send in my filter, run it whole last week without clearing the water. Decided to add DE into filter (based on recommendations from pool school) but DE didn't stay in filter it is now at the bottom of my pool.
Could somebody offer an explanation why DE didn't stay in filter and maybe to pinpoint the problem with my water cloudiness. For reference here is my current water chemistry:

FC: 8.5
CC: 0
TC: 8.5
PH: 7.6
CH: 100
TA: 125
CYA: 55 (this might be wrong, before cloudiness in the water it was 40)

Thanks,

 

[jmbradwell]

When you replaced the sand, did you inspect the laterals? You could have a cracked lateral.

 

[crkva]

I did check the laterals, and they were fine.