Anglers seeking bass on the fly rod within impoundments have virtually two options.

Option 1 is best when water is rising; the angler employing a floating fly line to sneak the fly into edges where vegetation or good drop off sections will hold searching fish. In August and September, in Somerset Dam, this was the killer method.

Option 2 is the main stay; schooled fish are located with a sounder and the fly is worked through them once it's down there. With depths fished ranging any where between 10 and 20m there's a strong requirement for the fly line to sink quickly and uniformly in order to avoid any belly or sag, which could cause a bite to go unheeded once the short strip retrieve commences.

I recently fitted up a fly reel with one of Rio's weight forward deep 7 (WF7S7 to quote full title) fly lines to assess the line's suitability for deep bass work. I'd heard some very good reports about the Rio offering and on surveying the supple, black, line it's very slim profile – for a 7 weight - immediately impressed me. Other fast sink lines I'd used previously were somewhat stiffer, and somewhat thicker, too, by comparison.

Once I had the fly line connected to a reels backing, a couple of casts in the yard told me that it was superbly capable of holding a big fly in the air with ease. Surprise, surprise, it cast very easily with a 6 weight - and an 8 weight - outfit as well so it's certainly versatile.

On Somerset Dam on a cool morning the suppleness of the Rio Deep 7 came to the fore. I've chased bass with a fast sink fly line on plenty of occasions previously and on mornings when a warm jacket was necessary the constant need to sort out tangles in the fly line was part of the morning's routine. I found the Rio Deep 7 remained very easy to work with even in cool conditions!

Long easy casts were followed by the line immediately sinking full length straight out of sight and it was just a matter of counting down to achieve the desired depth rate before stripping the fly back.

A look at the sink rate of the Rio is interesting. According to the makers the Deep 7 is rated as 7-9inch/sec (17.8- 20.3cm) which is slightly faster than the universally used S.A Striped Bass Type IV, claiming a sink rate of 3.75-6.5 inch/sec (10.5-17.5 cm).

In all, I consider the weight forward Rio Deep 7 to be well worth considering by the angler seeking bass or other fish well below the surface. These lines are a full 100 feet (30.5m) long and have a beautiful feel about them. They cast like a dream - a tangle free one in cooler weather – and are obviously a premium product.