welcome to the site crbbrb and nice looking fish there.
I would definately try going down in leader size and using a flourocarbon leader. Costs a little more but you will find a higher catch rate.
Even berkley fireline crystal down to the hook would be worth a go.
What size and sort of line are you using now?
PS: What sort of digi camera are you using also - nice clear pics there.
Cheers.
THE BIG GT.