goldfish is sullen at bottom of pond; then suddenly races about breaching the surface. Parasites?

Answer 1

An oxygen problem certainly sounds like the most likely answer. But as others point out it could be a parasite problem as well. Follow copperheads very sound advice on not treating until you are sure of the diagnosis.

One note of correction, Maracyn is not the correct treatment for parasites. Maracyn is an antibiotic and will do nothing for a parasite problem. Maracide is a good choice for parasites.

MM

Answer 2

Is it scraping against the sides of objects in the pond? That would be a confirmation of parasites.

If it's just surfacing then going back under, it could be an oxygen problem as the first answer suggests. It could also be that your fish is feeding on insects at the water's surface or just above that are using the pond as a place to lay their eggs.

Not every situation is a medical condition and you shouldn't medicate unless you can identify a specific need (and the correct cause) for doing so - especially given the volume of water that would require treatment in a pond.

Answer 3

Not a shortage of oxygen, else it would not be sullen at the bottom of the tank. Seems more like a internal parasite. You have to start treating with Maracyn.

http://www.goldfishinfo.com/medicate.htm

:-)

Answer 4

Sounds like low oxygen levels to me.... I would check the oxygenation of your pond and maybe try adding a bubbler or two. I would also try testing the chemical levels in your water as well to make sure nothing is out of balance.