Is this sand or DE Powder?

[Hon7483]

We had pavers put in at the beginning of summer and vaccum keeps filling up with this. Is it Polymeric sand or de powder? How can I prevent it from getting in the pool? I would appreciate any help on this.
Thank You!

 

[jblizzle]

Looks like DE to me.
You will have to open up the filter and figure out what is messed up in there allowing the DE to get to the pool.