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Expert advice on all types of fishing situations & tackle.
Sea Mainline Monos
Our Sea Mainline Monos collection gives anglers a broad choice of monofilament spools in common sea sizes, colours and spool lengths so you can match line to rod, reel and method. Gerrys stocks popular branded options and value spools for everyday shore and boat use, all selected for consistent diameter and breaking strain.
What we stock
We carry clear, hi‑vis and coloured mono in a range of breaking strains from light shore lines to heavy mainlines for rough ground. Options include short 4oz spools for trial rigs and larger 500 m spools for regular sea work. Brands and specific products are shown on the category page so you can pick the exact line you prefer.
Why choose mono mainline
Monofilament remains the most popular mainline for UK sea anglers because it offers stretch for shock absorption, good knot strength and forgiving handling when casting and playing fish. Mono is also easier to manage on the spool than some braids and is less likely to cut into rod rings under load. For many shore anglers a 15–30 lb mono is a practical starting point, with heavier 35–50 lb options used on snaggy or tidal marks.
Choosing the right mono
Match breaking strain and diameter to the ground and species: lighter mono for clean sandy marks and flatfish, heavier mono for rocky marks and larger cod or conger. Consider colour: clear or pitch black for stealth, fluorescent or hi‑vis for distance marking and bite detection. Also think about spool size — longer spools give you more line for long casts and deep water work.
Practical tips from Gerrys Fishing
