Agree with Eriegardless with using mono on inline boards and in the cold water crank bite.We use 15# Maxima Ultragreen mono.Most guys use 12# mono due to being closer in diameter to what the dive charts read.I go with a little heavier line because i spool a buddy's rods and he is a bit of a novice.I dont seam to have any problem with the 15# diameter in regards to figuring out depth with the dive charts though.