On one day they can be the most obliging fish that swims, taking baits like they are going out of fashion, another day - that to all intents and purposes is exactly the same as far as conditions are concerned - and you can't buy a bite. Yes, I know that applies to all species at times, but crucians are past-masters at the art of deception. Even when they are willing to bite they can take with such delicacy it needs the most exacting presentation on which to register the bite.

But above all, crucian fishing is really good fun. Most of the methods of fishing for them are a pleasure to use. They usually live in beautiful waters, and the fact that they present the ultimate challenge to get them on the hook makes them all the more interesting Add to that a spirited fight on the right tackle and you have an adversary worthy of the attention of any angler.

Crucians are often found in small ponds and while they are numerous in such waters they rarely grow to much more than about 8oz or so. The problem is that they tend to spawn more successfully than usual, and with a lack of predators in such waters their numbers multiply until they become terribly stunted, to the point where many of them are misshapen, with twisted spines and other deformities. They thrive much better in larger waters of two acres or more, sharing the water with other species like common carp and tench. The other species then help to keep the numbers down by consuming large amounts of crucian spawn before it has time to develop, and then eating many of the surviving fry.

Crucians can grow to 5lb and more in the very best waters, but many of the so-called crucians that make headlines are in fact brown goldfish, or a cross between crucian carp and common carp. The most distinguishing feature of the crucian is its lack of barbules on the mouth, unlike the common carp which has two. Brown goldfish are have deep serrations on the spine and dorsal fins, whereas the crucian has very shallow serrations. Although it must be said that unless you have examined both species you wouldn't know which one you are looking at, so mistakes are understandable. Hybridisation then complicates the issue to the point where only dissection can truly resolve the problem. But take the philosophy that I do - get out there and enjoy your fishing and only worry about if it's a hybrid or a brown goldfish if you catch one to beat the record.

Crucian carp are lovers of margins, wandering along the ledge below marginal vegetation like lilies and amphibious bistort. But this doesn't mean that distant swims should be ignored, just that the present trend of fishing for common carp at great distances is usually totally unnecessary. A groundbaited swim in a suitable depth of water anywhere within a couple of rod lengths of the margins will sooner or later attract their attention.

One of the greatest problems with crucians isn't to do with finding where they feed, or creating a feeding spot, it is in keeping them feeding for long enough to make a decent catch. They have a bad habit of feeding in short bursts and then moving on to the next swim, or simply moving on. They just can't keep still. But the good news is that it won't be long before they return to your swim for another burst of feeding. Usually, this performance of short but frequent visits to the swim is the pattern for the day, and you can often set your watch by the regularity of the visits. I've found that each visit by the shoal is long enough to catch two to three fish before they move on. Time between visits varies from 15 minutes to an hour or so, no doubt depending on how hungry they are that day, how many other baited swims they visit, and how far they wander before they turn round and make their way back. On the very best days the time between visits is extremely short, almost to the point where they hardly vacate the swim at all.

Groundbaiting for crucians, no matter what you use, will not alter this wandering pattern, which does not mean to say that you should throw any old rubbish into the swim. Good groundbait will attract them more quickly, keep them feeding for longer, and bring them back more quickly. I use my own brand of groundbait called Marden's Magic (available from Mr Wriggles, Telephone / Fax: 01787 379282) which is mainly crushed hemp and crushed trout pellet, with one or two deadly additives, mixed 50/50 with plain brown crumb. Half a dozen golf ball size pieces and a few catapult pouches of hemp, maggot, caster and sweetcorn are introduced at the start of the session, and then I top up with a couple of golf ball portions plus loose feed each time they vacate the swim. I've tried throwing the top-up groundbait into the swim while they were still present but this has more often than not resulted in them making a premature departure. So all I introduce while they are actually in the swim is loose feed.

They love a variety of hookbaits, ranging through maggot, caster, sweetcorn, bread flake, redworm, lob tails, mini boilies and several less common baits such as cockles, mussels, cheese paste, etc. Like their swim-wandering nature, however, they also wander from one bait to another, rarely sticking to one preference for any prolonged length of time. Tench are another that indulge in this annoying habit. It is amazing how often you can tempt another bite from them simply by changing the hookbait. Of course, they have favourites, the bait that catches most fish most of the time, but you will be missing out on a number of fish if you never try anything else, even if only occasionally, when the favourite is attracting fewer bites than it normally does.

I use a 13 or 14ft match rod for float fishing and an 11ft Quiver-tip rod for legering. Main line is 2.5lb and hooklength 2lb. Hooks, spade end, vary from 20's to 10's, depending on the bait.

Float fishing is the preferred method for catching crucians, for this method is often the only way you will see a bite from them, and although I don't fish with a pole myself I would think that it would be the best method of all. Float fishing is not always best though, but more of that later.

Crucians have this almost unique ability to mouth the bait without moving it, and then moving along the bottom very slowly. The result is that all you see, if anything, is a slight lift of the float, and then a drifting to one side or the other which can easily be mistaken for the drift of the water it is so subtle. When they move towards or away from you the bites are even more difficult to see. The lift method has little success, for the lift method has to use a fairly substantial bottom shot to work correctly, and crucian carp will not tolerate excess weight, even when finely balanced with the float and the remainder of the shotting. Also, the lift method depends on the bottom shot being lifted, and this just doesn't happen often enough, or with sufficient emphasis, when crucians are the target. Ordinary laying-on float fishing techniques also suffer in the same way and for almost the same reasons.

It seems that, most of the time anyhow, the most successful float fishing rig is one that has the depth set exactly to the depth of the water, with the hookbait hardly scraping bottom (or even very, very slightly off bottom) without any line whatsoever laid on. The nearest shot to the hook, no heavier than a No. 4, should be as close as three inches away, and, unless there is a heavy drift, the only other shot should be locking the float. In a drift the bulk shot needs to be at mid-depth. Loaded floats are good when there is no drift. The float should be dotted right down to the point where it is difficult to see. Then, when the crucian mouths the bait and gently drifts to one side it pulls the float under as the line follows its own curve in the water. Or, if the crucian does lift the bait slightly, along with the nearby small shot, the float will then be sensitive enough to respond and rise slightly through the surface, which is of course a more obvious movement when the float is dotted right down.

Many times you will see the float dancing and gyrating at the surface, and often these are the most difficult bites to hit. I think the cause of many of these bites is the shear sensitivity of the rig, in that it is set so delicately the mere waft off the crucians fins with cause it to give erratic movements. Always worth trying when this happens is a change of bottom shot position, either further away, or closer to, the hook. Also, changing the depth by a mere inch, deeper or shallower, can make a considerable difference too. There are days when, to make a successful strike, you have to hit the fish when the float is moving along the surface, other days when you have to wait for the float to go under, and yet other days when it is best to hit them when the float rises slightly.

Using float fishing methods like the one I've just described does not present a bait that is absolutely stationary on the bottom. Even when there is little or no drift the turbulence created by nearby fish, feeding or not, can be enough to make the hookbait, and therefore the float, move around a little. It appears there are days when this is the crucial factor where crucians are concerned, for on those days they will not take a bait that is not lying still on the bottom. Enter legering and the quiver-tip, and a personality change for the crucian! For the bites suddenly become so bold they can drag the rod off its rest.

For sensitivity there is nothing to beat a simple paternoster, where the bomb or feeder comes off a short 6in to 9in link combined with a 2ft to 3ft long hooklength. The junction is a water knot, so there is not even the weight of a swivel involved. Fished with the lightest quiver-tip you can get away with, or a swing-tip, you have a very sensitive set-up. When I want to present them with a partial bolt-rig I use the loop method, with a short loop, and a heavier quiver-tip.

So there you have it. Crucian fishing can be deadly subtle with almost invisible bites, to something much more obvious with blatant bites. You just never know, not only from one day to another but from one hour to another! They are a species that demand you ring the changes in both tackle and bait in order to keep one step ahead.