
I just finished typing my post and then I wiped it, here we go again...
Tetrafin is heavily marketed in the UK too. I wouldn't touch the basic range of flakes and pellets foods for goldfish, but I have tried their "premium" range foods. I have used Tetrafin Gold Japan before. I found it to be a reasonably good quality food and readily accepted.
I like the fact that it is supposedly especially formulated to meet the nutritional requirements of fancy goldfish. They are called sinking "mini-sticks" which are basically little pellets which soften and sink quickly, although I still pre-soak them. I have alternated using them with Hikari products.
The ingrediants listed are pretty standard and don't state "whole" fish ingrediants, just "fish and fish derivatives"

although to be fair it does also claim to have a high vegetable content. The Protein level is listed as 47% which is good and the Ash at 8% which isn't the highest I've seen to be fair.
Personally, I think I would class this as a medium to high quality food and a good attempt at providing a better quality of goldfish food than others on the market.
I would recommend that people give it a try and see what they think for themselves
http://www.tetra-fish.co.uk/tetragoldfish/...etrafinfood.asp