Been a while since I pulled boards or ran the down riggers. When I did, I used 20# stren, clear. No issues there. Casting, I've been using Pline either moss green or clear in 15#. Can't say I've seen any difference in catch rates between the two. I also use 14# fireline with a fluro leader on my jig stick. Catch just fine with that too. Those are almost all night fishing. I did use the jig stick some last year throwing at jumps and they hit the jig just fine. A number of years ago I did use 20# fireline for planers during the day. That did make a difference. Couple of trips running half the rods with the stren and the other half with fireline. Never even got a hit on the fireline rods.

Andrew