Although this post is 2 years old at this point, and the author may never check it again, I will post what happened to his fish to the best of my experience, and perhaps others may benefit from it.
Your convict most likely came into contact with an anaerobic bacterial infection through a small cut in the mouth which spread quickly to his brain and gave him a quick death--usually only takes 2-14 days depending on the fish and wound size.
How this happens is in heavier piles of substrate and underneath ornaments (such as your big reef castle), anaerobic bacteria may form during periods of abnormal oxygen and nitrite shifts.
When the victim fish begins moving this infected substrate around, if he has any open wound in the mouth, he'll will be capable of obtaining this bacteria in the wound--which will, in turn, spread very quickly through the face and eyes, and kill the fish rather abruptly. I lost a few fish to this issue in years past--primarily during spawnings when substrates were being rearranged most.
This bacteria is aggressive, and you must act within the first 24 hours of spotting it, or there is virtually no hope. The only things I have seen work in the least bit was Methronidazole or Chloramphenicol treatments--which may still fail. I actually saved a fish once by resorting to cutting the tip of the poor gal's nose off--she scarred a little, but survived.
Preventive measures should be taken to reduce the chance of anaerobic bacteria reaching the mouth of a fish. First is keep the substrate spread out and not too deep! Cichlids love to dig, and AB loves to hide in the deep parts of the substrate. Something as simple as a broken tooth can leave the wound and mouth susceptible to falling victim to bacteria. Next, always make sure to gravel vac underneath those large ornaments. I recommend redecorating every month to keep those ABs from having a chance to develop.
Anyhow, this is a horrifying bacteria for any hobbyist to come across. In most cases, it is more ethical to euthanize the poor fish, rather than to watch its face rot off in a few days if you fail to catch it in time.
I hope no one has to face this monster, but if you do, at least you will have an idea of what you're up against.
Good luck!
Your convict most likely came into contact with an anaerobic bacterial infection through a small cut in the mouth which spread quickly to his brain and gave him a quick death--usually only takes 2-14 days depending on the fish and wound size.
How this happens is in heavier piles of substrate and underneath ornaments (such as your big reef castle), anaerobic bacteria may form during periods of abnormal oxygen and nitrite shifts.
When the victim fish begins moving this infected substrate around, if he has any open wound in the mouth, he'll will be capable of obtaining this bacteria in the wound--which will, in turn, spread very quickly through the face and eyes, and kill the fish rather abruptly. I lost a few fish to this issue in years past--primarily during spawnings when substrates were being rearranged most.
This bacteria is aggressive, and you must act within the first 24 hours of spotting it, or there is virtually no hope. The only things I have seen work in the least bit was Methronidazole or Chloramphenicol treatments--which may still fail. I actually saved a fish once by resorting to cutting the tip of the poor gal's nose off--she scarred a little, but survived.
Preventive measures should be taken to reduce the chance of anaerobic bacteria reaching the mouth of a fish. First is keep the substrate spread out and not too deep! Cichlids love to dig, and AB loves to hide in the deep parts of the substrate. Something as simple as a broken tooth can leave the wound and mouth susceptible to falling victim to bacteria. Next, always make sure to gravel vac underneath those large ornaments. I recommend redecorating every month to keep those ABs from having a chance to develop.
Anyhow, this is a horrifying bacteria for any hobbyist to come across. In most cases, it is more ethical to euthanize the poor fish, rather than to watch its face rot off in a few days if you fail to catch it in time.
I hope no one has to face this monster, but if you do, at least you will have an idea of what you're up against.
Good luck!