I can assure you that when the pH is at 8, chlorine production is at an absolute minimum. What little that is produced is immediately used up before it can get into the main body of the pool.

The only way to find out if there is any Cl production, is to sample from one of the return jets. I use a 3/4" flexible hose pushed into the return, and the other end into a sample bottle, under water.

The cell could start scaling up making things worse, as it is a new pool.

The 10 ppm more than likely came from the liquid chlorine added. Until a complete water analysis is posted, everything is speculation at this point.

Keep on adding the acid to maintain the pH from 7.2 - 7.6, brush, brush, brush, and vacuum to waste. This will take time, so persistence is needed here. Hang in there.

Pat