I have 10-12 reels to spool up and I have a ton of older mono to use as filler . I bought flourocast but at the price I'd just as soon not fill the spools with it. How many yards of "good line" would you tie the knot at ?
I usually do 100 yards. Try to buy 300 yard spools and then get 3 fills out of it. Plus with braid, I reverse the line one time halfway through its life assuming there is plenty left. I also use backing so that the spool is nice and full after the 100 yards is on.