suitable 'pond' for goldfish?

Hi, would like some advice as to whether a 230 l plastic tub 54 cm deep or 275l tub 34 cm deep is at all suitable for keeping 4 large goldfish in (in the south of the UK). Digging a pond is not an option, due to concrete courtyard. Do I really need to try and find a bigger container or get a 'proper' above ground pond? If anyone can suggest a source of a suitable larger container I'd really appreciate it. Have read a lot of conflicting advice about what environment they'll need, so would appreciate any advice!
thanks
Kate
http://www.mindscapetherapies.co.uk

katem

Look at hockeyref88's pond ust posted.
Might be just what you need only smaller.

If you'd like an idea about how to build an above ground pond, check out my pond I just built over an existing concrete slab. Any questions feel free to ask.

2008_0315kenssiding30015.JPG