I apologize that no one has responded to your question sooner. Different experts come online at various times. I just came online and saw your question. My name is ***** ***** I’m a biologist with a special interest in fish. I'm sorry to hear of this problem. I cannot respond directly to your email or your phone - it is against policy unless we make special arrangements.
The best thing you can do on your own is provide special baths. A bath is where the fish is placed in a special solution for short periods of time, then returned to the pond. The goal with baths is to have the fish lay the eggs or reabsorb them. Epsom salts are the only thing that has been found to help with that. Most goldfish keepers use 1 tablespoon of Epsom salts per gallon of water. Leave the fish in the bath for 15 minutes each day. I wouldn't add any Epsom salts to the tank. Instead use Maracyn according to the package directions to prevent infection from any retained eggs. You can also feed her thawed and peeled frozen peas. The Epsom salt baths, Maracyn in the main tank, and feeding peas will be the only measures you can take.
If you want to consult an aquatic vet, more can be done. There are hormones that can be give to cause her to pass her eggs. Pituitary extract is one. There are two other hormones that are also used to induce spawning. They are luteinizing release hormone and HCG ( a human hormone). All of the hormones are by prescription only, and have to be obtained from a an aquatic vet. The hormones are injected. You can read more about them here:
Here is where you can find a fish vet:
If you have more questions, just let me know. I hope that whatever you decide to do, your goldfish will be fine.
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