Susan - I frequently hear the comment about not being able to compete for
food as a negative for fancies/red caps in a pond. In a pond I dont believe
this is a concern because of all the algae available, even if it doesnt get
hand fed. Mine has gotten MUCH bigger in the few months that I have had it,
it seems very happy & active and color is great. In fact I would say it is
flourishing. I recently met a local ponder who has a least one in each of
4 small 100-200 gal preforms. She claims hers seem to be growing better
than the fan tails she also has.

I do have some concerns about predators but for now I hope I am not being
irresponsible. I do have numerous plants, lilies and a ledge as a hiding
place. I know this would probably not deter a heron but being relatively
urban, thus far I have only seen a possum (insect eater) and an egret miles
away. My walls are about 6 inches high even when the pond is completely
full.

Your Pearl Scale - I had a Orange Crowned Pearl Scale as well. Alas, I
found out too late she did not belong in a pond. Not sure if it was being
in a pond in general or fish problems I had which affected her internally
and thus unsolvable for a newbie. But while she was with me she was an
amazing little fish. Have you seen them. Like a Pearl Scale, but I think
the tail is a little bigger and the head is I believe cross bred from an
Oranda. Mine had an orange wen and the large round head like an Oranda. I
hope to have another some day in an aquarium. The only slight deterrent to
this plan is I believe they take a little more tank than many fancies
because they can get quite large. I love the Orandas/Orange Crowns because
they seem to seek your attention rather than flee from you. My Orange Crown
would occasionally let you hold her in the water. Incredibly I read of one
guy who claimed his would actually play with him. It was large, but he
would put a small styrofoam ball in the aquarium and it would head butt it
out.
In any case I guess we all figure out pretty rapidly, they are not just
pond/aquarium decorations. So I can certainly understand/support your
feelings of not being able to properly take care of them in a pond.
Have Fun!!
Bill Brister - Austin, Texas