which size tub is best for goldfish pond?

Hi,

I am going to make a garden pond using a multi tub (large plastic tub) for goldfish. I have the option of 2 sizes.

1) 275l/61 gallons, 112cm diameter, however, only 34 cm deep.

2) 230l/51 gallons, 85cm diameter, but 54 cm deep.

Is 34cm (well, less than that as won't fill it to brim) going to be too shallow for goldfish in the winter?

Would I be better with the smaller deeper one?

Finally I have read several different things about how much space goldfish need (surface area vs length of fish vs depth of pond and total capacity being most important). I would be really grateful if someone could advise me on how many fish I could have in each size tub, or best way to work it out.

I would like to give them the opportunity to grow to 12", how many years would this take, and I ideally would like 4+ fish, would these pond sizes be enough for 4 to be happy?

Many thanks for your help!

Kate
http://www.mindscapetherapies.co.uk

katem