Maybe this can help with ideas till someone gets on
@Humblefish
Internal parasites/intestinal worms:
Symptoms - Internal parasites are worms which live inside and damage a fish’s intestines. As a result, the main symptom is white stringy poop. It has to be white;
brown stringy poop, for example, can just mean intestinal irritation which requires no treatment.
Treatment options - It is preferable to
food soak a medication in this situation, as opposed to dosing the water. Food soaking delivers the med directly into the gut where the worms live. In order to food soak, you should also use a binder (ex.
Seachem Focus) to prevent the medication from leaching out. Binding also makes the treatment
reef safe.
Knowing which medication to use can be tricky as there are many different types of internal parasites to consider. For example, tapeworms are best treated using praziquantel whereas only metronidazole will eradicate Hexamita. I personally have had the most success using
metro; however I will be experimenting with fenbendazole in the future. Below is a list of medications to use; in most cases you can dose them into a QT or food soak:
- API General Cure (contains both praziquantel and metronidazole)
- Prazipro
- Seachem Metroplex (dose every other day or use 1 scoop of Metro & 1 scoop of Focus in 1 tablespoon of food. Add a few drops of saltwater and mix well.)
- FishVet Metro-MS or Hikari Metro+ (same as using Metroplex)
- Dr G's De-Wormer (contains praziquantel) or Dr G's Anti Bacterial (contains kanamycin & metronidazole) frozen fish food. It would be optimal to feed one in the morning, the other in the evening, for full coverage.
Due to the resilience of these critters, it is recommended to treat (or food soak) for a
minimum of 10 days or up to 3 weeks.

When using a prazi based product, you can
initially only dose once; however a second dosage should be administered 7-10 days later. Do a 25% water change beforehand.