The issue is Dave that in a Koi pond, there is a lot less water area and natural biological filtration than in a river or much larger lake. It is the laws of dilution. If you overstock a pond with an acre surface area, then the same problems would occur as overstocking a domestic pond of much smaller size. If the biomass exceeds what the natural filtration can handle then problems occur.
The only reason that the Australian Government class carp as "invasive" is that they are not thought of as a "sport" or "good eating" fish there, where as in Europe they are classed as a sport fish in almost every country as well as "good eating" in Eastern Europe. Same as in the USA, they are not classed as "sport" fish because they are not targeted using imitation lures like Bass, Walleye, Muskie, etc are. The Asian Carp are a completely different species and the way they have infested a lot of the river systems in the USA is one key reason for regulations regarding the stocking of fish, native or non-native in to non-enclosed waterways. The EA and DEFRA/CEFAS in the UK will through the book at anybody being caught stocking fish without paperwork into anywhere other than a PRIVATE pond or fish tank, and even then there are regulations to ponds within 100 metres of a natural waterway due to risk of escapee's due to flooding or other wildlife removing the fish from the pond.
Another problem weve now got is KHV in our fishing lakes where did that come from , its believed it came from the movement of Carp between lakes from France to the UK as you know they get to a massive size and are a fish to catch , if you read the latest you'll find its all over the UK with the angler blaming us koi keepers.
( Wow just getting reports of a massive 8.6 earthquake in Chile with risk of tsunamis on the BBC).
The original question was
"I'm wondering if someone knows about koi regulations in CT.
I have pond with stream going in and out.Its been brought to my attention that it might be illegal to have koi in situation like this .I'm new to this and it's never crossed my mind.
I remember seeing koi or gold fish in big pond in a center of Hartford, seen it in pond with stream at nearby golf course.
Wondering if it's legal" and basically the answer to that question is no for the reasons weve given between us
Dave
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