If she is eating then start feeding her food that is soaked in epson salt. There is a pinned article about this at the top of the page by RD titled Treating Hexamita aka Spironucleus with Epsom Salt Solution. I would use this feed for 10-14 days. If the fish is still eating it usually works. If the epson salt food doesn't purge out all the worms then I would move on to feeding her food that is soaked in CZ Clear Medication. If she won't eat the food soaked in Clear then I would use the small syringe the clear medication comes with to inject the medication into her stomach.
No garlic will not rid parasites. Garlic is typically used as an attractant in fish food. But it can really only be used in very small amounts due to its potency.
