On the subject of pond fish, one can find oodles of online information
regarding goldfish and koi. And potentially various loaches, for detritovore
activity on the bottom.

But... what kinds of freshwater fish are algae eaters and generally safe
for ponds, in a comet/koi environment, and with the temperature swings
that are more commonly associated with ponds.

I can find lots of algae eaters for freshwater aquaria, but these seem
to like unrealistically high temperatures.

Thoughts/ideas?

C//