We have 20 Blacktip Reef Sharks ( Carcharhinus melanopterus ) in 400 m3 tank. We have had them for over 1 year now but lately, I have noticed their chin getting fat and unusual. It looks like they have a tumor(i send you some of their pictures). Beside that, They are doing fine and eating nomal but i'm so worry. I dont know it's just they are too fat or it's a disease sign. I looked up everywhere but I cant find anything the same.I hope you can give me some advices. Here is condition of my tank: pH: 7.8, Ammonia: 0 mg
/L, Nitrite: 0 mg
/L, Nitrate: 0 mg
/L, Salinity: 29 ppt, Temperature : 29 OC. its tankmates are 9 stingrays, 14 small turtles and 5 whitetip reef sharks (whitetip reef shark 's chin are nomal ) We feed the sharks with fish and feed them once in 2 days. please help me! Any advice from you guys would be appreciated.
i dont know how to upload pic in this site so i give you the link online. http://nn8.upanh.com/b6.s28.d2/3edcb...28.dsc0007.jpg