Black Ghost Knifefish with tubular pinkish discharge from behind jaw

Question
55 gal. tank has been set up for about 1 year. Two kissing gourami, 1 Pearl gourami, 1 placco, 3 small bala sharks, 1 blue gourami. The filter is an Aqua Clear filter.  10% water change every two weeks.  Large Diatom filter is run once per week for 24 hours.  BGK has had this discharge for about one week. He was out during the day when the light was on but now he only comes out at night when the light is off.  He is fed cut up frozen shrimp, freeze dried blood worms and flakes.  He is not as active as he has been, obviously not himself.

Answer
Hi Angela;

He may have injured himself. He is feeling insecure so he is going back to his natural habit of being nocturnal and hiding. Sometimes BGK's will squabble with plecostomus at night for hiding places. Make a few extra ones so that doesn't become a problem. He may have banged himself after a fight you didn't see.

Keep the tank water very clean so he can heal. A 25% water change every week is what's really needed all the time, along with gravel vacuuming. A 10% change every two weeks is really not enough to keep nitrates (NO3) low. It builds up over time and can keep fish from fighting off disease. You might want to do a 25% change right away and then another in 3 days. This will help him feel better and boost his immunity. It also reduces the number of bacteria and fungi naturally occuring in the tank water that could infect the open sore.

I hope he feels better soon....

At Your Service;
Chris Robbins