The tench in our lakes are not monsters but many have recently been seen to have some serious injuries to their mouths. Like all tench they have quite soft mouth parts.
Members have been observed using very strong tackle when fishing for tench on our large lake, such as is more suitable for barbel fishing on the Wye, or for large carp.
Many fishery owners advocate a minimum main line strength on their lakes where tench are present. Often a minimum 8 lb bs main line is specified. The reasoning behind this is that it helps reduce the number of line breakages when playing a tench so that fewer fish are left with a hook and line attached to them. This is probably a legacy from a time when barbed hooks were the norm, not the problem here but is more likely to be one of the causes.
Although it does not look like it recently, Treowen large lake is a vey weedy and a tench is inevitably going to make for the weed as soon as it is hooked.
Now we all experience hook pulls from time to time but we have to try and avoid this as much as possible. This is where the correct tackle and playing skills are essential.
A rod that is too strong will not absorb the shock forces imposed on the hook and mouth of a lunging tench as well as a more suitable rod will do. A very strong line will not give nearly as much. (There is no place for braided main lines here). The combination of the two encourages some anglers to drag a weeded tench free with excess force on the fishes mouth.
There are many rods available for tench fishing, and bearing in mind that you are not going to catch a double here, one with a test curve of 1 lb, or 1.25 lbs maximum, is about right. An Avon style rod will do just as well. I would say that a main line of 8 lbs bs with a weaker hook length is as big as anyone should use. Hooks should be at least a size 8 or 10 barbless and wide gape to attain a good penetration and a firm hold. Ok, may be a bit smaller when fishing with corn.
Using such a combination of tackle and skill will help prevent most fish from getting deeply weeded. A weeded tench will nearly always swim free if the line is allowed to go slack or nearly slack. As soon as reasonable movement is seen, tighten up and the situation will be back to normal.
If a weeded fish cannot be moved out and it sheds a barbless hook, all the better than applying excess force.
There is some evidence that when float fishing, as opposed to ledgering, a tench is more likely to be hooked in its top lip than in the weaker corners of it mouth. Having tried both methods I personally have found that overall I catch just as many tench on float tackle as on a ledger. And I enjoy it much more.