Crater and bulging eye on the left side of my flowerhorn's face. What disease is this?

[biohszard_star]

Hey guys, my flowerhorn has a big crater on the left side of his face, just beside his left eye. The crater has been progressively growing larger for the past couple of months. Recently, I've noticed that his left eye is starting to bulge a little bit. I've been previously using Metronidazole & Mebendazole (soaking his food pellets in them) to try and treat him, but they aren't working. His appetite remains unchanged, and he's still as active as ever. I'm afraid that will change if his disease keeps on worsening. I've attached pics for reference:

- Tank size: 50 gallons
- Water parameters: All within normal levels; API Freshwater Master Test Kit used to test
- Aquarium setup: Freshwater
- Aquarium setup time: 1 month; my fish was previously in a 25 gallon tank before I put him in this one
- Other fish/plants in tank: No other fish/plants in the tank
- Aquarium temperature: 29 C
- Filter Used: Eheim classic 350
- Last water change: last week; 30% of the water changed on a weekly basis
- Exposure to sunlight: No
- Food type used: Pellets every other day: no live food
-

 

[kno4te]

Would try putting some methylene blue in the crater area. Keep the water clean. Is your water hard?

 

[islandguy11]

Agreed you should treat that as a topical infection not an internal one, in this case I don't think the Metronidazole & Mebendazole are really doing any good (and could likewise be adding unneeded stress which is actually slowing the healing process).

Also when you say normal water parameters what are your nitrate levels usually like? With that size FH and that size tank a 30% weekly water change is kinda ok but personally I'd be aiming more toward a 50% change, this too will likely aid the healing process, as will adding some salt.

 

[duanes]

I agree, sounds like bacterial infection, brought on by too high nitrate.
If it were me, I'd be doing 2 to 3 water changes of about 40% per week, trying to keep the nitrate level less than 10ppm.

 

[squint]

Never use metronidazole for a bacterial infection in fish. Nearly all are Gram negative aerobes. That means no metronidazole, no amoxicillin, and no erythromycin.

 

[biohszard_star]

Apologies for the late reply.

Would try putting some methylene blue in the crater area. Keep the water clean. Is your water hard?

I'm pretty sure our water supply is soft. I'm applying Methylene Blue to the water before water change. I'm afraid of applying it directly. If I were to do that, what would be the best way of doing so?

Agreed you should treat that as a topical infection not an internal one, in this case I don't think the Metronidazole & Mebendazole are really doing any good (and could likewise be adding unneeded stress which is actually slowing the healing process).

Also when you say normal water parameters what are your nitrate levels usually like? With that size FH and that size tank a 30% weekly water change is kinda ok but personally I'd be aiming more toward a 50% change, this too will likely aid the healing process, as will adding some salt.

Right. I increased the frequency of water change to 50% 3x a week, as per your suggestion. Ammonia and Nitrite levels are 0ppm, whereas Nitrate is at 10ppm.

Never use metronidazole for a bacterial infection in fish. Nearly all are Gram negative aerobes. That means no metronidazole, no amoxicillin, and no erythromycin.

I stopped using antibiotics and switched to just Methylene Blue, but I think the crater is just getting bigger. I'm afraid it might spread to the area supporting his eyeball. Is there anything else I can try, aside from that medication?

 

[kno4te]

Try dipping a qtip in the MB and directly applying to the fish. You’ll have to take the fish out of the tank.