Here is an exert from an article on safe handling of carp for C&R. It is from an English carp angler.
Nets, Mats, Sacks and Weigh Slings
"If you are fishing for carp then you should have an appropriately sized net, 42’’ is the recommended size but on commercials where the carp are all under 15lbs then a 32’’ will suffice. The mesh should be soft and fairly deep and the arms of the net should be easily detached from the spreader block. The handle should be of around 6 feet in length and for ease of use it should be light and rigid.
A quality unhooking mat is a must, so many shops sell small thin ones but these are only any good for Roach fishing! A Carp mat should be at least 50mm/ 2†thick foam and should be large enough for specimen Carp (approx 4ft x 2.5ft) or alternatively of the polyball type, there are no poor polyball type mats on the market to my knowledge so these would seem a safe choice.
Weigh slings should be supportive and secure, the rigid pole type ones are ideal and should always be zipped up at each end to prevent the fish from sliding out, they should feature a special material inside that prevents mucous loss but not always. These are ideal for use with weigh crooks and are perfect for returning the fish to the water
The use of forceps is often recommended to the beginner or novice but in my opinion this is unwise for it takes much more skill to use forceps without causing damage than it does to use your fingers or in extreme cases, side cutters to cut the hook . When the use of forceps becomes the norm there is the risk of imparting too much force and damaging the soft mouthparts of the Carp, much more control is gained by using the fingers and if it takes a while so be it, it is never wise to rush
Treatments for wounds to the body or mouth of Carp are commonplace in anglers kit and although there is no record of these ever causing harm to a Carp I believe that it is perhaps better to let nature run its course. There are many times during a Carps life when it will receive much the same injuries in the wild, for example Spawning will remove scales and cause lesions much more severe than most anglers would cause and the Carps natural diet of shelled creatures will regularly rip its mouth to shreds. We are anglers not vets or doctors and I personally believe it unwise to interfere. Personal Verdict: Personal choice.
Playing it safe
In the majority of Carp fishing situations the angler receives a ‘Run’ and thus the carp will be hooked or at least lightly hooked, subsequently when the angler lifts the rod there will be no need to ‘Strike’ to set the hook, a tightening of the line until the rod has a steady bend will ensure the hook is driven home with firm but limited force. When the rod continues to bend as the fish powerfully tries to evade capture the correctly set ‘Clutch’ or ‘Drag’ of the reel should allow line to release in a manner that is balanced between the tackle being used and the power of the fish. When using heavy tackle more force may be applied on the fish in order to control it quicker and steer it from snags or weed where they will inevitably head for, but when using light tackle it is required to go easier on the fish and let it run a little more thus lighter tackle should only be used when the risk of a fish finding snags or weed is significantly low. When using heavy tackle a strong fish also requires an element of freedom as more of the power exerted will be transferred directly to the hook hold and in turn could cause damage to the fishes mouth.
The anglers choice of mainline has a profound effect on the amount of pressure is exerted on the fish, ‘Braided’ lines have almost zero stretch and so will transfer virtually all force directly to the fish. It is wise to only use braided lines in the situations where they are essential or at least very much needed. The reels drag settings will be in constant alteration to succeed in landing any fish hooked using braid. In my opinion braided lines should only be used by experienced anglers. Monofilament or ‘Mono’ lines have a degree of stretch that will increase as the distance between angler and hooked fish increases and gives an often vital cushion against the often very spirited fight of the Carp, it is still very wise to alter the drag settings during the fight to optimise the balance between tiring of the fish and pressure on the hook hold.
It is vitally important to net a Carp in water that is deep enough so if this means getting wet then so be it, the net should be in place before the Carp is drawn towards it. There should be as much line between the tip of the rod and the fish as possible and when the Carp is drawn into the net it should do so on its side with only its mouth slightly out of the water. As the net is lifted around the fish take a break, there is no rush if the water is deep and well oxygenated and a little breather will help you to concentrate on what comes next.
Short term retention
When you net a carp You should have all the things needed to deal with it ready and waiting on the bank. However if like me you are disorganised and lazy there is nothing wrong with leaving the fish in the net for a short time, it is quite probably of benefit to the fish after a hard tussle. It is however not always possible and there are certain criteria to be met that will decide whether or not short term retention is a good idea in any given situation.
The water should be deep enough to fully cover the fish, ideally deep enough to ensure it needn’t make contact with the mesh.
The marginal water should be cool and well oxygenated, on hot sunny days I certainly wouldn’t recommend retaining a fish for very long if at all.
The net should be firmly secured to the bank, I use a bankstick through the spreader block to ensure the fish cannot swim off with my net and quite possibly meet an unfortunate end.
Ensure with regular checks that the fish remains upright at all times but refrain from lifting it out unnecessarily to show other anglers/passers by. It should NEVER be left unsupervised.
There should be no large rocks/structures that could lead to the fish damaging itself if it should become eager to attempt to escape the net.
The fish should sit there quite still and calm if undisturbed but if it does become agitated and struggles then its retention should be cut short.
Long term retention
This practice is known as ‘Sacking’ and whilst I do believe that it can be carried out with pretty much zero risk to the fish I also strongly believe that it is unnecessary in 99.9% of Carp fishing situations. It involves a specialised and dedicated ‘Carp sack’ which the carp is placed into and secured inside in very deep margins or a suitable distance out into the lake. It should be firmly secured to a bankstick or a tree etc by a strong rot proof cord/rope. Basically there should be absolutely no way that the carp can pull itself loose as if that happens it is certainly going to mean curtains for the carp. I have never used a sack myself and don’t think I would ever need to.
I firmly believe that only very experienced and serious anglers should retain a Carp in this way and only then for very important reasons, it certainly shouldn’t be done for the sake of something as ridiculous as a daytime photo or to show an expected visitor.
When removing a Carp from a sack after a considerable time it is also important that your handling skills are extremely well honed as the fish will be refreshed and very lively after such a long rest, poor handling skills could very well lead to a badly damaged fish in this situation. Personal Verdict: Unnecessary.
Removing a Carp From the water
Ok so you have caught a carp....Well done!..It's sitting in the net or sack and you have that warm fuzzy feeling. Of course you do! And why not, its what you came for after all! Retention whether short term or long term as stated earlier CAN benefit the carp IF done properly. So why not take the time to relax yourself and enjoy the feeling that success brings.
So everything is to hand around the mat, you have situated the mat on even ground with a nice backdrop for your picture, the weighsling, scales and other bits and bobs are all well within reach...why not have a nice bucket of lake water handy too? In hot weather this is essential as the fish will dry off quite rapidly. The photos look better if the fish is nice and wet and free of dirt, leaves and white foam. The white foam incidentally may be a sign that the fish is starting to dry out so we slosh this off with nice cold lake water at regular intervals, i like to do so between every photo.
I'm taking it for granted that you have a photographer ready as self takes are definitely not a good idea for beginners and those confident enough to do it won't need to be reading this! Get him to pull his weight! As you will now need to make sure EVERYTHING is wet, mat, sling, EVERYTHING the fish touches should be wet, this includes your hands and possibly even your clothes! Talking of hands it would be a good idea to remove wristwatches etc that may damage the fish as you hoist her up for a mugshot
Right all is wet and all is to hand you can now start to think about removing the fish from the water. The mat area should be as close as possible to the lake to limit any mishaps when carrying fish and there are several thought processes that i normally have at this time. Firstly i will make sure there is no unnecessary obstructions between lake and mat and secondly if there are natural obstacles then you must decide how you will go about navigating them whilst carrying a heavy and delicate fish.
If the fish is in a sack then you simply MUST get in to remove it, its not good to be dragging a fish out of the water. You must make sure the fish is in an upright position with all fins laying flat to its body. It must be in the bottom of the sack with its head into one of the bottom corners. Now you must take up all of the excess sacking by rolling it down till you meet the top of the fish's back. Sacks can and do break so you will need to either put the sack into a weigh sling or if its a stronger type sack you should think about gently supporting the fish underneath its body. Personally i wouldn't carry a sack, i'd rather use a weigh sling to transport the fish about should i ever sack a fish.
If the fish is retained in a landing net then the same is best, remove the arms from the pole and roll them down to the fish and take the same care when carrying the fish to the mat.
On the mat
Right then the carp has been placed on the mat and if shes lively she might flap about a bit. There is no excuse for a carp that leaps off the mat, preventing this should be you very first priority. Second priority is damage limitation, The mat may well be soft and deep but it ain't as soft and supportive as the water the fish came from. Some anglers seem to think its OK for the fish to flap about as long as it is on the mat! I feel this is ignorance as the fish can still damage itself both externally and internally. So i like to prevent the carp flapping about by keeping it covered by the wet mesh or the flaps attached to the mat, I'm almost certain it is the sunlight that causes this as the don't seem to go quite so bonkers at night and covering the head (and eye) does seem to help quite considerably. If the carp does start to twitch or writhe i simply apply pressure to both ends of its body. Never push down on the middle of the carp, one because you could cause damage and two because it seems to make them flip even more! I think the second point proves the first!
Another thing to remember is never sit the fish upright on the mat, its organs are delicate and they really seem to dislike this, I'm not 100% sure how risky this is to be honest but i know when something looks wrong! Also keep a good eye on the fins to make sure they are not put under any pressure.
It is important to be confident about handling a carp as confidence gives a cool head and allows more rational decision making, its no good going all 'butterfingers' and 'scatterbrained' when you are responsible for a magnificent fish!"
Dom "Welsh80"