I currently have a small, modest water feature in the one part of my
garden not overgrown by trees or the need to maintain a lawn for the
kiddies to play in.....Because of the way that the drainage is dealt
with by the house it is one of the few areas where I can dig deep enough
to get below the frost line......

Right now it has a small water feature - a reservoir that goes up an
artificial hill (the garden is flat) and then comes back down again and
feeds up again etc. etc......the reservoir at the bottom is around 2 ft
6" deep.....the whole thing is pretty close to the house....

We've had some severe weather recently for this part of the UK.....so I
decided to find out how frozen the reservoir had got....OK it is covered
by a grill with rocks that will give some degree of protection.....the
ice was less than 1/8 inch thick.....now could I risk extending this
with a shallower pond and using this as my maximum depth (as it is
already dug out)?.....or should I be adding a bit more for
comfort?.....If my max depth is maybe 3 foot in this area (which would
be around 18" circumfrance (sp)) would this give sufficient protection
for goldfish (not Koi) to be able to over winter without any loss?

TIA
Gill