Float line

A float line connects the gun to the float at the surface. When a fish is shot the diver lets go of the gun and surfaces; the fish fights the float, not the diver, and the gun cannot be lost. The alternative is a reel on the gun, which most rock hunters prefer; in open water and for big fish, the float line is the safer system, and many divers use both.

A float line also tethers the float to the diver, so that the flag stays over the diver and the float cannot blow away.

Three kinds:

• Bungee line: a stretchy core in a dyneema sheath, 10 to 20 m relaxed and stretching to twice that. It absorbs the run of a fish, does not float on the surface in loops, and is the modern standard.
• Floating line: hollow polypropylene or a cored line that floats so that it cannot wrap around rock below you. Cheap, visible, tangle-prone in surge.
• Plain rope: no. It sinks, snags and cuts.

What matters:

• Length: about one and a half times the depth you dive. 15 m for shore work in 10 m, 25 to 30 m for walls. Too long is loops and tangles; too short pulls the float under and lifts you off the bottom.
• Strength: rated well above the biggest fish you will meet; 200 kg or more.
• Clips: stainless snap clips or, better, a tuna clip at the gun end that opens with one hand, and a swivel to stop the line twisting.
• Visibility: a bright colour you can see against the bottom.

One and a half times your working depth. Add a short leader with a clip at the gun so that the gun can be unclipped to hand it to a buddy or to change shafts.

Rinse, inspect the sheath for cuts on rock, and check the clips for corrosion and for springs that no longer close. Replace at the first cut through the sheath: the bungee inside is what is holding the fish.