Recognizing Ich
Symptoms: tiny white salt-like spots on body and fins, flashing (rubbing on objects), clamped fins, lethargy. Spots appear and disappear on a 7–10 day cycle as the parasite goes through its life stages.
Catch ich early — it spreads fast and can kill an entire tank within 2 weeks if untreated.
Understanding the Life Cycle
Ich has three stages: trophont (visible white spot on fish), tomont (free-swimming reproductive stage that drops off and divides), and theront (newly hatched parasites that infect new fish).
Medications only kill the free-swimming theront stage. The trophont under the white spot is protected. This is why treatment must continue for 10–14 days minimum.
Heat + Salt Treatment
Slowly raise tank temperature to 28°C (82°F) over 24 hours. Heat speeds the ich life cycle and causes parasites to hatch faster. Goldfish tolerate heat short-term but watch for stress.
Add aquarium salt at 1 teaspoon per gallon. Dose dissolved salt slowly over 24 hours. Salt damages the protective coating of theronts.
Continue for 10–14 days. Increase aeration — warm water holds less oxygen.
Medication Treatment
For severe cases, use Seachem ParaGuard, API Super Ick Cure, or copper-based ich medications. Follow package directions exactly. Remove activated carbon from filter (it absorbs medication).
Goldfish are scaleless-sensitive — use half-dose for safety. Some medications stain silicone — accept this or use a hospital tank.
Prevention
Quarantine all new fish for 2–4 weeks before adding to main tank. Avoid temperature swings (the #1 ich trigger). Keep water quality high. Stress-free fish rarely get ich even when exposed.