I dont keep my line on for more than 4-5 trips for my casting reels and 7-8 for my spinning reels, and i replace it all at once, to me its not worth losing a fish due to old weak line. the crystal ivory i use comes in big spools so i dont worry about wasting it...
Tyler
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All Americans believe that they are born Fishermen. For a man to admit a distaste for fishing would be like denouncing mother-love and hating moonlight. -John Steinbeck