I like to have extra graduates, so I buy them cheap, in quantities of 5.

I mix 1.25 liter of working strength fixer at a time, and then re-use it until my calculations and tests indicate it is exhausted. My preference is to divide it into two equal batches, and then use each batch, one after another, for the clearing time.

Your tank will indicate how much chemistry you need to cover the film sufficiently in order to ensure even development. Use that amount. I would be surprised if you will need 600 ml, unless you are shooting 120.

Your dilution calculation is done correctly, but I doubt you will be able to measure the HC 110 that accurately, unless you use unnecessarily expensive equipment. If you do actually need 600 ml, 19 ml of syrup diluted to 600 ml in total should be fine. You may want to consider, however, using a higher dilution such as E (1+47 or 1+49 for simplicity) or H (1+63), in order to use longer times, and less syrup per roll.

Photo-flo needs to be cleaned carefully from plastic reels, because otherwise it can gum them up. I and many others tend to take the film off the reels before it goes into the Photo-flo.