Question
Hello,
For the first time, we are going to put fish in our 80 gallon pond that is 9'
deep and about 3'5" in diameter. We will get a pump and filter but am
wondering two things:
How many small goldfish can we put in of the 2" variety?
What is the minimum temperature they can survive in without being brought
indoors?
I understand they will need a place to hide from raccoons and the neighbors
cat, so will provide plenty of "cover" for them.
I used to have a 50 gallon aquarium years ago so have some experience with
fish.

Answer
If your pond were 9 feet deep, it would be 649 gallons and quite a strange pond! I assume you meant 9 inches deep which would make a pond of 51.6 gallons with the 3'5" diameter.  Goldfish grow quickly so a 2 inch one can grow over a foot in a few years.  If your pond were an aquarium, I would say to have no more than 5 or 6 goldfish.  In a pond, it would be even fewer.  So, start with just a few fish.  Goldfish can take water down to freezing as long as it doesn't actually freeze (33 degrees F).  Since the pond is so shallow, if you have a real winter there, you'd have to bring the fish in for the winter.  A heater or de-icer could keep it open if it only rarely gets ice.  It depends on where you live.  The shallow pond will also get warmer faster in the summer (could overheat the fish) and will make it super easy for predators to get the fish.  Cover can be made with live plants, pots, and things like that.  If a raccoon shows up, it will make a mess and probably get some fish.  At that point, you'd have to net the pond to protect the fish.  My raccoon knocked over some pots last night; they like to make a mess!  Good luck!

Robyn
fishpondinfo.com