Can you please give me a good reference for the knots used to tie flies onto monofilament line? The normal knot that I have always used for years on a heavier monofilament line has always been fail safe. However, I have found on 2-4lb line, the knot I have been using slips and I have lost a couple of my flies.

I suggest that you have a look at our Knots Directory. Here you will see how to tie most of the popular knots. For tying flies to tippets, I would recommend the Trilene Knot. It is easy to tie and is very strong. I suggest that you try different knots, find one that suits you, learn to tie it properly and then stick to it. Terry Lawton

Could you give me some advise on the best backing to attach to a shooting head? I was given the name flat beam or something like that. Many thanks. Pete Taylor

Like many things in fly fishing, there is a good choice of different backing lines to use with shooting heads. One man's wonder backing is another's nightmare. You want a backing that is as memory-free as possible - so that it does not come off the reel in tight coils - that is tangle-free and well lubricated so that it will shoot well. Orvis makes the flat beam shooting head backing that you mentioned. Rio has introduced a floating backing line that may also be worth considering. Vision and Loop also sell special running lines for use with shooting heads, as do Cortland and Scientific Anglers. Although I have no personal experience of fishing with a shooting head, I do know that Amnesia has always had a good reputation. It has been on the market for some time now and so may not be quite so high tech as newer products. Terry Lawton

Can you advise me on the best book or video to guide me in learning how to perform the double haul casting technique, please? At the moment I have to do too many false casts to work the line out to 20-25 yards, and due to having to aerialise so much line cannot cast any further than this and have poor control. I saw the double haul" technique performed the other day and it looked like a much more efficient way of casting down to the backing without having to aerialise a lot of line! Steven Whitney

We are about to publish a new series on casting and one of the article will be on the double haul. If you try to aerialise too much line and do too many false casts, the resulting presentation cast will be a disaster. Weight forward fly lines are designed to be cast with only the first 30 feet aerialised. Many anglers could reduce the number of false casts for almost every cast. For example, if you make four false casts regularly, try using only three. Mel Krieger's book, The Essence of Flycasting, and Ed Jaworowski's book, The Cast, are both good. Krieger has videos as well. You should be able to buy either book from Coch-Y-Bonddu Books. Terry Lawton

Doing some window shopping for carbon fly rods in the magazines I became aware that the question of carbon "grading" is somewhat obscure! I have read numerous articles about rod actions etc. but have not seen any articles relating to the carbon blanks. Looking at say Ron Thompson rods these are advertised as IM6, IM7 and IM8 - how does this equate in real terms to weight, action, cost etc and what does the terminology refer to? Added to this literally and metaphorically by other manufacturers are things like SiC whisker and kevlar. I would be interested in your reply - maybe material for an article for one of your experts? Philip Metcalfe

Your e-mail raises some interesting questions and I will certainly think about writing an article in response. In the meantime you may be interested in reading Don Phillips' book, The Technology of Fly Rods, which I have reviewed for Fish & Fly. Although this book goes only so far, it is probably the best available at the moment. The references to IM6 or IM7 carbon is to do with the modulus of the material used to build the rod, the idea being that the higher numbers are higher modulus, and thus stiffer fibres, which will produce faster rods. Whisker composite technology is, very briefly, to do with discontinuous carbon fibres. The individual, continuous fibres that make up rbon fibre are broken so that only a few fibres are effective in any given plane. A rod made this way retains its tensile strength and stiffness because adjacent intact fibres take up the load of a broken fibre through shear forces transmitted through the resin. Terry Lawton

I have recently looked in my fly boxes and have discovered small black dots everywhere and my flies are disentigrating! Any ideas what they are and how to treat my boxes so that this doesn't happen again. If they are mites do I disinfect the boxes and start my fly collection again? Jeff Barnes

I have never heard of the problem that you have got with your flies and fly boxes. If the dots are mites, and, as you say, your flies are falling to pieces, I would think that it would be best to scrap them and if the boxes have ethafoam lining, replace those as well as the flies. If you tie your own flies, you can always re-use the hooks from the old, infected flies. I don't know whether somebody from your local Environment Agency office could help identify the problem positively. Terry Lawton

To help answering your question I spoke to Ian McCormack of Greys of Alnwick. In essence if a rod has a single line rating ie 6#, that rod will be rated for a 6# weight forward line, for the simple reason that the sale of weight forward lines far exceeds those of double taper lines throughout the world. If you use the same rod with a double taper line, you could go down one weight. For rods with dual line ratings, 6/7# for example, then that rod will perform best with a 6# double taper line and a 7# weight forward. The reason for this is that the weight of double taper line aerialised when casting will be slightly greater than that of a weight forward line as the double taper line has a thick belly whereas with the weight forward, the weight is in the head. Lines are rated by the grain density of the head and there can be very slight differences between seemingly or essentially similar lines made by different manufacturers. You may well find that your casting style and the use to which you put your rod will effect its performance. You may find your rod performs better with a line of a different weight, either lighter or heavier than the manufacturer's recommendation. Terry Lawton

Could you possibly send me a list of patterns that are best for catching pike as I would like to try this as an alternative to trout fishing? Brian Heald

If a pike is hungry it will not be too fussy about what fly you use. Fly fishing for pike is still developing and there are not that many recognised patterns on the market. Many big, gaudy flies are sold as pike flies and will catch fish if, as I have said, the pike are feeding. I suggest that you start with a small selection of different colours and styles of fly and see which seem to be the most effective. Have a look in Fulling Mill Flies' catalogue (www.fullingmill.com) You might also like to read my article at www.fishandfly.co.uk/tledit1000.html Terry Lawton

I was fishing on the river Itchen a couple of weeks ago and caught some grayling and also some very nice brown trout. One of the grayling had blood spots which seemed to be seeping very slowly from under some of its scales and if I wiped it away, it reappeared. I don't think it could have been an injury as this was in various places over the fish. Could it possibly be a disease? Any clues would be appreciated. Colin Russell

In an endeavour to come up with an answer to this question, I contacted Ron Holloway, a very well-known former river keeper on the Itchen. First of all, he pointed out that not every fish caught will be in the best of health. There are sick fish in all rivers and fish that are near the end of their natural lives. he could not make a diagnosis from your description of the fish that you caught. He said that he has never seen an Itchen fish showing the symptoms that you described. His advice is that if you catch another fish with the same symptoms that you take it to a fish scientist for a proper examination. You should contact the local office of the Environment Agency. Do keep the fish damp for as long as possible if taking it for examination. Terry Lawton

I have recently started fishing for Grayling on the Welsh Dee. I am unsure of the correct methods when presenting weighted nymphs or wet flies such as the Kee-Hee or small spider patterns fly. I nomally cast up and across on a dead drift, allow the cast to swing and then retrieve slowly and also use a 3' sinking leader with a floating line. Any advice on techniques or locating grayling would be greatly appreciated. Josh

I don't think that we can do any better than recommend that you read Ronald Broughton's book The Complete Book of The Grayling, a new edition of which was published by Robert Hale last year. I have reviewed it for Fish & Fly here. It costs £35 but is an excellent work for anyone who is at all serious about fishing for grayling. There is a section on the Welsh Dee and the book includes chapters on all the methods of fishing for grayling world wide, including the best flies. Terry Lawton