Acan with Brown Jelly?

Peer.Boerner · 2026-09-14T12:52:11-0400

Is this brown jelly disease? Had this Acan too close to a frogspawn. Any suggestions how to treat??

Oscar47f · 2026-09-14T12:57:51-0400

Hard to tell kind of… if it’s like disintegrating into a brown sludge then yes it is… you can identify the ciliate using a microscope… or otherwise take the coral out and gently blow water on it with a turkey baster and if the coral blows off then likely it is brown jelly… to treat do daily dips in potassium salt based dip (polyp lab makes one) or a hydrogen peroxide solution… make sure to blow off as much of the jelly as you can during the dip DO NOT blow it off inside the tank or itll spread… hope that helps !

Peer.Boerner · 2026-09-14T12:59:41-0400

Oscar47f said:
Hard to tell kind of… if it’s like disintegrating into a brown sludge then yes it is… you can identify the ciliate using a microscope… or otherwise take the coral out and gently blow water on it with a turkey baster and if the coral blows off then likely it is brown jelly… to treat do daily dips in potassium salt based dip (polyp lab makes one) or a hydrogen peroxide solution… make sure to blow off as much of the jelly as you can during the dip DO NOT blow it off inside the tank or itll spread… hope that helps !

Many thanks. I’ll take it out and gently blow with turkey baster. I don’t have potassium salt dip but I do have peroxide and also seachem reef dip which I think is iodine based.

Saltyreef · 2026-09-14T13:01:14-0400

Looks like its just sucumbed to coral warfare. Move it away from the frogspawn and keep an eye on it.
Melafix works great as a coral dip and rehab from coral warfare. Its like franks redhot sauce, put that crap on anything

Peer.Boerner · 2026-09-14T14:04:10-0400

Saltyreef said:
Looks like its just sucumbed to coral warfare. Move it away from the frogspawn and keep an eye on it.
Melafix works great as a coral dip and rehab from coral warfare. Its like franks redhot sauce, put that crap on anything

many thanks as well! Really appreciate the prompt guidance! I’ll have to get some Melafix. I haven’t bought anything for me reef since this morning :)

EnterName · 2026-09-14T14:44:38-0400

Brown Jelly Disease (BJD) is most likely not a single specific disease, but rather a symptom of different diseases or issues with the coral. What they appear to have in common is that you can observe certain ciliates (namely Scuticociliates like Philaster sp.) when you put the brown jelly under a microscope (Sweet et al., 2013). However, treating these ciliates turned out to be ineffective against similar diseases (Sweet et al., 2014), and people figured out that the actual primary pathogens causing coral deaths were bacteria like Comamonas testosteroni (Willans & Bradshaw 2021) or Vibrio sp. (Sweet et al., 2013). The ciliates are just opportunists that feed on zooxanthellae and seem to cause the brown jelly, so they are secondary pathogens and not as harmful.

This means that when two corals sting each other, the very same opportunistic ciliates can show up and profit from the dying tissue and the released zooxanthellae. That can still cause similar brown mucus, but it is not the same as an actual BJD that kills corals. I have observed this first hand on various corals that stung each other in my tank, all of which fully recovered. In some cases it was ciliates (see page 8, post #144), and at other times it was just diatoms, cyanobacteria, or dinoflagellates accumulating on the dead tissue.

If the coral was healthy and just got stung, it should recover without any further issues once separated. Corals are used to this in nature. If you see more tissue recession and brown mucus, an actual treatment might become necessary, but that requires antibiotics like Ciprofloxacin, which hobbyists like to use, or maybe something like Ampicillin, which was tested very successfully on similar diseases in the literature (Sweet et al., 2014).

Long story short: Separate the corals, and it's probably fine. Keep observing. If it gets worse, you have to decide whether you want to set up a quarantine tank and find a vet that is willing to prescribe antibiotics, or you can try some of the commercially available products against STN, RTN, and BJD. Whether those actually help is beyond my knowledge.

Peer.Boerner · 2026-09-14T15:50:48-0400

EnterName said:
Brown Jelly Disease (BJD) is most likely not a single specific disease, but rather a symptom of different diseases or issues with the coral. What they appear to have in common is that you can observe certain ciliates (namely Scuticociliates like Philaster sp.) when you put the brown jelly under a microscope (Sweet et al., 2013). However, treating these ciliates turned out to be ineffective against similar diseases (Sweet et al., 2014), and people figured out that the actual primary pathogens causing coral deaths were bacteria like Comamonas testosteroni (Willans & Bradshaw 2021) or Vibrio sp. (Sweet et al., 2013). The ciliates are just opportunists that feed on zooxanthellae and seem to cause the brown jelly, so they are secondary pathogens and not as harmful.

This means that when two corals sting each other, the very same opportunistic ciliates can show up and profit from the dying tissue and the released zooxanthellae. That can still cause similar brown mucus, but it is not the same as an actual BJD that kills corals. I have observed this first hand on various corals that stung each other in my tank, all of which fully recovered. In some cases it was ciliates (see page 8, post #144), and at other times it was just diatoms, cyanobacteria, or dinoflagellates accumulating on the dead tissue.

If the coral was healthy and just got stung, it should recover without any further issues once separated. Corals are used to this in nature. If you see more tissue recession and brown mucus, an actual treatment might become necessary, but that requires antibiotics like Ciprofloxacin, which hobbyists like to use, or maybe something like Ampicillin, which was tested very successfully on similar diseases in the literature (Sweet et al., 2014).

Long story short: Separate the corals, and it's probably fine. Keep observing. If it gets worse, you have to decide whether you want to set up a quarantine tank and find a vet that is willing to prescribe antibiotics, or you can try some of the commercially available products against STN, RTN, and BJD. Whether those actually help is beyond my knowledge.

Thanks to you as well! (I read and value many of your posts). Inteeestingly, I moved the Acan away from the frogspawn and already it’s looking much better. I suspect as you propose this is not BJD after all.

EnterName · 2026-09-14T16:09:59-0400

Peer.Boerner said:
EnterName said:

Brown Jelly Disease (BJD) is most likely not a single specific disease, but rather a symptom of different diseases or issues with the coral. What they appear to have in common is that you can observe certain ciliates (namely Scuticociliates like Philaster sp.) when you put the brown jelly under a microscope (Sweet et al., 2013). However, treating these ciliates turned out to be ineffective against similar diseases (Sweet et al., 2014), and people figured out that the actual primary pathogens causing coral deaths were bacteria like Comamonas testosteroni (Willans & Bradshaw 2021) or Vibrio sp. (Sweet et al., 2013). The ciliates are just opportunists that feed on zooxanthellae and seem to cause the brown jelly, so they are secondary pathogens and not as harmful.

This means that when two corals sting each other, the very same opportunistic ciliates can show up and profit from the dying tissue and the released zooxanthellae. That can still cause similar brown mucus, but it is not the same as an actual BJD that kills corals. I have observed this first hand on various corals that stung each other in my tank, all of which fully recovered. In some cases it was ciliates (see page 8, post #144), and at other times it was just diatoms, cyanobacteria, or dinoflagellates accumulating on the dead tissue.

If the coral was healthy and just got stung, it should recover without any further issues once separated. Corals are used to this in nature. If you see more tissue recession and brown mucus, an actual treatment might become necessary, but that requires antibiotics like Ciprofloxacin, which hobbyists like to use, or maybe something like Ampicillin, which was tested very successfully on similar diseases in the literature (Sweet et al., 2014).

Long story short: Separate the corals, and it's probably fine. Keep observing. If it gets worse, you have to decide whether you want to set up a quarantine tank and find a vet that is willing to prescribe antibiotics, or you can try some of the commercially available products against STN, RTN, and BJD. Whether those actually help is beyond my knowledge.

Click to expand...

Thanks to you as well! (I read and value many of your posts). Inteeestingly, I moved the Acan away from the frogspawn and already it’s looking much better. I suspect as you propose this is not BJD after all.