Knot to shorten a buoy tether line?

Posted by ChowSaidWhat@reddit | sailing | View on Reddit | 12 comments

I use a 25m length of 4mm line as a tether between my anchor and a surface buoy. Anchoring depths vary between 5-15m. When I'm in shallow water (say 5m), I end up with \~15m of excess line. I use a weight and a small cage to keep the line down, but I'd rather shorten the line properly at the buoy end before dropping it. What knot would you recommend for taking up the slack? Ideally something I can tie/untie quickly and that won't jam on thin line.

Daisy chain? Series of butterfly knots? Something else?

Thanks