6 Inches F/8 Reflector Telescope What Kind Of Fish Will Survive The Winter In A Pond Zone 8 (coldest 20 F -8 C)?

What kind of fish will survive the winter in a pond zone 8 (coldest 20 f -8 c)? - 6 inches f/8 reflector telescope

Currently I am up to 6 dragons that guppies do not last the winter and think that a lot of them in winter.
I thought a couple of small goldfish (fan tails), add but I'm not sure if the timing is good because it with the 6 Comets (4-7 inches [10 to 18 cm]) and competing lines of Fans 1.5-2.5 inches [4-6cm]
Pond is approximately 8 cm diameter from 1.5 to 2 meters deep.

Can I safely add the queues of fans.

What could be more specific, preferably with a little color.

What kind of scavage can add and / or need.

What can I do to protect the fish from predators such as herons or raccoons too. A blue heron away all the fish this year and do not have bird food koi $ $ comets seem almost too beautiful for a fraction of the cost.

What kind of live fish such as guppies can in the winter?

If I save a little guppies in order for the next summer, a small tank that you receive from us with more than half a dozen guppies (4 men min 2Female) can