The common carp (Cyprinus carpio)

[NorthernRaider]

One of the Eco groups to whom I occasionally get E mails from report that last years tiddlers (around 25mm to 30 mm) they kept in a modest sized pond of approx. 15ft by 9 ft by 4ft6 deep are now weighing between 2 and 2.5 pounds, they reckon in another year or so they could be over 4 or 5 pounds. Being " green" types they are not doing as other commercial growers are doing and feeding the carp trout pellets which eventually ( so they say) damage the carps internal organs, they feed them on a wide assortment of more natural foods from grain to bloodworm, maggots, bits of fruit, wholemeal bread to ornamental goldfish pellets so the fish have a good broad ranged diet.

The beauty of carp is they do not need heating ponds, just a damn good deep point at least 4 ft down to over winter in, the deeper and better insulated the better. They also enjoy plenty of aquatic plants to hide in and to chomp on as well. they don't need and don't like crystal clear water, but for the happiest and best growth they don't want to be swimming in their own filth either so SOME sensible biological filtration is essential as is GENTLE water flow to help airiate the water.

Most other species require warm water, or highly oxygenated water or highly filtered fast flowing water all of which use lost of energy and kit.

If you are thinking about growing fish for food the Carp is king as its native to Europe and has been farmed in the UK since medieval times.
( most monasteries kept Stew Ponds to grow carp in and many village ponds original role was for growing carp)