Had a friend ask me if the fish can seeyour line and what should he be using. Said he was fishing within 3 ft of another buddy and that guy was getting hits almost instantly where his line would have to sit a spell. Told him I didn’t know cause I just use what I got. If I catch that’s ok and if I don’t that’s ok too. Told him I would post and ask the pro’s about it. He fishes mainly for sheeps and red fish.
Wait til buddy reels in then cast to buddy’s spot…that and ask his buddy what line he’s using. 
Flourocarbon is virtually invisible. However, I have some spots I fish that if you throw on the spot, you get a red, 2-3 feet to either side and NADA. Could be a hole or structure holding fish there.
don’t think that that matter to much, if they are there and hungry they will eat.
I believe in clear, thin line. Some people don’t think it matters, and that’s totally fine with me. 
Gotcha Covered,
Lee Strickland
Strickland Marine Insurance, Inc.
843-795-1000 / 800-446-1862