I'm sorry if that sounded dissmissive - not intentional.
As far as the pump, it depends. Are you planning to dose the dichlor into the skimmer and let it dissolve on top of the sand? How often and for how long do you run it on timer? Could you divide the run time into two or three periods a day?
When you have a chance run the FC CC pH and TA so we can see where we are.
Use up the dichlor you have on hand to maintain FC. When it's gone, put on the SWCG, wait a few days and test CYA then figure the plan to bring your CYA up to desired level using Granular CYA.