Well, this is again the false information which circulates in the web and even in many books. To repeat it: Silurus glanis don´t reach lengths of 5m. This dates comes only from a handfull of old stories. I checked their background and looked for scientific dates about the sizes of Silurus in this regions and there was no indication that they would grow there especially big. Furthermore the the length-weight-relation is completely false for this alleged specimens. A hypothetic 5m wels would weigh easily well over 700kg. To stay at facts, the heaviest confirmed specimen was 144kg, and it was highly exceptional.
If you look for photos of the wels you will find many big and even some gigantic specimens. But look at the sizes, none of them is over 3m. The ones over 2,5m are already extremely rare, and the bigger ones even more. If this species would really reach 15 feet, don´t you think it is strange that you can´t find one of at least 3m?
The 2,78m specimen was really abnormal, and it was a monster. You won´t hardly ever get something like this in your aquarium or pond, perhaps only if you keep it in warm water and feed it all the time for decades and also only if you get a specimen with exeptional genetic conditions.
whoa
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