Pool Pump Won't Prime

I had my pool pump and filter running just after opening, it took a bit to prime but it was running.  I had to run some chemicals for high phosphates for 24 hours, then I cleaned out the DE filter completely, reassembled, and now the pump won’t prime.  If I fill the basket with water it sucks it from the basket, but I can’t get it to pull suction from the pool.  Any thoughts or ideas what could be the issue?

I also have kind of same issue, I haven’t find a solution yet. My post: https://www.inyopools.com/Forum/thread/pool-pump-looses-prime-within-1-minute-of-starting-pump/