My initial chemistry results : pool size 17000 gals FC 1 TC 2 CYA 40 other results with in acceptable levels.

I shocked with 3 lbs calhypo 48% next day reading was FC 3 TC 4 . Shocked again with 4 lbs Cal hypo 56.8%. Next day reading FC 17 TC 18. When I added chlorine last night i ran the pump overnight at low setting ( i have dual setting pump 2HP pump,3 month old pool.high setting runs with clear O3ozonizer)...back up..we run our pump at least 8hrs/24 hrs 4hrs high setting 4hrs low.now the pool water is very clear...but CC is still 1...im using the TF 100 test kit.

pls help!