Ben,

Thanks for taking a look. I have just double, triple, quad, etc. checked at various points on many pipes on the system. The joints are of course larger and I am ignoring those. The main piping is basically 6" OD (circumference). A google check at https://www.plumbingsupply.com/info-pipesizes.html, does state that it is 1.5" PVC Pipes.

I'll check the pool chemistry and pump in required stabilizer and/or chlorine. Thx.

-d