[Peter Hewison]

whats a good mono in the 5lb bs.its to go on spare spool.

 

[Marq]

The lightest line i have used was 8lb by Rapala Not bad line

 

[Keith White]

If its for LRF then don't...

Buy a 5lb fluorocarbon instead as a first option.

Mono is a bit stretchy to let you detect bites on the drop. It's ok for retrieving but even then, it's stretch could mean you deep hooking a few fish.