Coral Brown Jelly Disease Treatment Guide: Iodine and Removal
The brown gelatinous slime crawling across a torch coral overnight is one of the most aggressive coral diseases in the hobby. Coral brown jelly disease can destroy a SGD 200 LPS frag in 36 hours if untreated, and it spreads through water-borne protozoans to neighbouring colonies. This treatment guide from Gensou Aquascaping at 5 Everton Park combines iodine dipping, mechanical removal and chemistry stabilisation into a recovery protocol Singapore reefers can run within an hour of spotting symptoms.
What Brown Jelly Actually Is
Brown jelly is a Helicostoma protozoan infection — a ciliate that feeds on coral tissue and excretes brown gelatinous waste. It thrives on damaged or stressed coral tissue and most often hits Euphyllia (torches, hammers, frogspawns), goniopora and trachyphyllia. The disease is opportunistic, so it usually follows a stress event rather than appearing without cause.
Triggers to Investigate
Recent shipping or fragging trauma, alkalinity swing exceeding 0.5 dKH, salinity crash below 1.023, lighting change without acclimation, fish bite damage, or chemical contamination from gear all precede brown jelly outbreaks. Identifying the trigger prevents recurrence after treatment. Test the full panel during the first hour and stock kits from the water care range.
Immediate Removal Step
Remove the affected coral from the display within the hour. Brown jelly releases protozoans into the water column that infect neighbouring corals. Move the colony to an isolation container holding tank water — a 5-litre tub with low flow works. Do not scrub or rinse violently as that traumatises remaining healthy tissue further.
Mechanical Removal of the Jelly
Use a turkey baster or pipette to gently siphon the brown gelatinous mass off the coral. Repeat until the visible jelly is gone. The siphoning should happen in the isolation container, not the display, because every disturbed jelly cloud spreads protozoans. A small hand-held siphon from the aquascaping tools range works well.
Iodine Dip Protocol
Brightwell Lugol’s Solution at 8-10 drops per litre or Aquaforest Iodum at label rate — dip the affected coral for 10-15 minutes. Iodine kills the ciliates without destroying remaining coral tissue. Watch for any sign of distress — rapid mucus production, polyp closure beyond expected — and shorten the dip if needed. Rinse in clean tank-temperature saltwater after the dip.
Frag Healthy Tissue if Necessary
If half the colony is already destroyed, consider fragging the healthy heads off the dying base. A bone cutter or coral saw cuts cleanly above the affected region. Mount the salvaged heads on plugs and treat them with a second iodine dip 24 hours later. Discard the heavily-affected base — recovery from severe brown jelly damage is rare.
Quarantine Period
Hold the treated coral in isolation for 7-10 days with daily observation. Repeat the iodine dip every 48 hours for the first three dips, then stop if no jelly returns. Maintain low flow and 30-40 per cent normal lighting during quarantine. Top off evaporation with RODI to keep salinity stable at 1.025.
Display Tank Treatment
The display itself does not need treatment if the coral was isolated within the first hour. If protozoans have already spread, dose the entire system with Aquaforest Coral Sentinel or Brightwell Coral Snow + RestoR per label. Run carbon in a media bag for 48 hours after dosing to clear residual chemicals. Browse media reactor options in the aquarium equipment range.
Reintroducing the Coral
Once 7 days pass without jelly recurrence, return the coral to a low-light, low-flow corner of the display. Watch for 14 more days before moving it back to its original placement. Polyp extension returns gradually — full poly behaviour may take three to four weeks. Resist the urge to feed heavily during recovery; a starved coral is healthier than a fed one with damaged tissue.
Prevention Going Forward
Drip-acclimate every new LPS coral over 60 minutes. Quarantine new corals in a separate frag tank for 14 days. Monitor alkalinity tightly. Avoid moving torches and hammers once placed because the relocation stress alone can trigger jelly. Iodine maintenance dosing at low levels — Brightwell Lugol’s at 1 drop per 40 litres weekly — supports tissue resilience.
Related Reading
emilynakatani
Still Have Questions About Your Tank?
Drop by Gensou Aquascaping — most walk-in questions get answered in under 10 minutes by someone who has set up hundreds of tanks.
5 Everton Park #01-34B, Singapore 080005 · Open daily 11am – 8pm
