Minni

Please can someone help identify this fish in my pond: about 6" in length, long and thin rather that a typical 'fish' shape. It is a browny/orange colour, more orange underneath. It has two larger fins on the underside of its body near to the head and two small fins near the rear end. It has one large fin on the centre of its back towards the rear. Its has whiskers around its mouth. 6 larger ones that stick up and two small ones under its mouth. It puts its whole mouth out the water periodically, perhaps looking for a fly. When it swims fast it twists it whole body, rather like an eel. My pond is only patio and when I bought the house 6 years ago it had gold fish in. The heron got them about 4 years ago and I let it go to a wildlife pond. There are frogs, toads and newts all living in the pond as well as 3 or 4 other fish which I haven't been able to identify. They are about 3" in length and a very dark brown in colour. They swim together. However, the fish I am trying to identify appears to be a one off. I first spotted it about 2 years ago and have only seen it half a dozen or so times since. Today it was basking in the sun at the top of the pond and I was able to fish it out and put it in a clear tank to try to identify it. Any ideas anyone?