I know salt water can play havoc with all sorts of tackle, I'm a bit confused about lines, what is the difference, salt water and fresh water lines, I have a rod and reel I keep just for salt water fishing, I have been using a Snowbee fresh water line now for a couple of years, it doesn't seem to have rotted, it still casts as well as ever, I don't always clean it after a fishing session, just rinse the reel and spool in fresh water, makes me think it's a sales gimmick, what are your thoughts on this...??

I use my normal trout gear when bonefishing - maybe I'm not good enough to notice the difference between it and 'proper' saltwater tackle.

Nothing other than the taper. Tropical lines are obviously designed stiffer to cope with the heat but COLD saltwater lines just tend to have steeper, more aggressive taper to turn over larger flies. In fact most cold saltwater lines hyped by Rio, Sa etc. are **** in cold water and you are better off with standard freshwater lines IMO. The Snowbee XS and Cortland 444XL are very popular over here. You might just have to cut back the front taper a bit if to long/thin.

Nothing other than the taper. Tropical lines are obviously designed stiffer to cope with the heat but COLD saltwater lines just tend to have steeper, more aggressive taper to turn over larger flies. In fact most cold saltwater lines hyped by Rio, Sa etc. are **** in cold water and you are better off with standard freshwater lines IMO. The Snowbee XS and Cortland 444XL are very popular over here and better than any purpose designed saltwater line that I have used. Just have to cut back the front taper a bit if to long/thin.

I'm still looking for the perfect Intermediate line for uk saltwater and I've tried pretty much all of them

if you can get a cammo 444 weight forward popular late nineties early 2000's works well enough in cold saltwater just doesnt sink as fast cause its saltwater!
also used old fast glass intermediate double taper from airflo, again works well enough.
bert