Question
My husband put in a small fish pond this summer and we have two KOI fish. The pond is about 12 to 14 inches deep, is this enough to keep them from freezing. I live in Northern Virginia and we SOMETIMES get as cold as 10 below. Also, do I feed them in the cold weather?

Answer
Congratulations on your new pond!  How big are the koi?  What are the pond's length and width?  Normally, you'd want a pond of at least 3 feet deep where you live to safely overwinter adult koi.  I live in MD.  My pond was supposed to be 3 feet deep but they builders messed up and made it 26" deep which has worked for my fish for 10 years.  A pond of only 12 to 14" though may be a problem.  If the koi are small, and we have a mild winter, and you can keep a hole in the ice with a de-icer, they might make it.  I would be more concerned when they're larger.  Koi can grow over 3 feet but most stay under 2 feet long.  They need water deep enough to have room to swim and so that they can remain below any winter ice.  Also, shallow ponds make the koi more likey to fall victim to predators such as herons and raccoons.  I really suggest having the pond dug deeper, at least a few square foot section to at least 2 feet deep.  If that's not possible, then you might be able to overwinter the koi for a few years before they grow too big to do so in that depth pond.  After that, they'd need a new home anyway if the pond is shallow.  My page on overwintering ponds is at http://www.fishpondinfo.com/winter.htm
If you add a de-icer, aeration, etc., the fish might be ok for now but I can't give you a guarantee.

Stop feeding the fish once the temperature is below 55 degrees F.

Koi experts such as those at MAKC suggest having 1000 gallons for the first koi and 100 gallons at least for each additional.  They are based in your area, lucky you!  You can join their group.  They can visit your pond and give advice.  You can also go to meetings and learn a ton if you have time.  Their web site is http://www.makc.com/

Good luck!