Okay, thanks FormerBromineUser. Some questions to clarify:

In order to get my pool to FC of 13, I assume I would have to add approximately 416 ounces of 8.25% bleach (13 x 32 oz). Then, in order to maintain a level of 13 ppm, I would need to figure out how much I lose per day and add that back.

Once I add the approximately 416 ounces, how long is appropriate to wait to measure FC to ensure I have it in the target range?

Also, should I worry about what is causing the 2 ppm per day loss or not?