Added Stingray, 75% Tank Dead in 2 Weeks. HELP!

[Seeker7911]

We introduced a fresh water teacup stingray into our 265 gallon, sand bottom tank. Within a few days we noticed the guppies and tiger barbs nipping at the very tip of the ray's tail. A cloudy white fungus began to grow just beyond his stinger. Before I could treat the fungus, the Tiger Barbs, Bala Sharks and Mollys started dying. They all exhibited the same symptoms; twitching (seizures), loss of equilibrium, erratic swimming patterns.

As soon as we started losing tiger barbs, I had my water checked by professionals. The water levels remained stable, no temperature spikes had occurred. They recommended a fungal treatment to help with the stingray's tail, but by the next day, he was dead. Shortly before he died, the ray shuddered, swam erratically, and lost his appetite. Half of my fish population, and the ray, were dead within 2 weeks.

What went wrong? Most importantly, how do I fix it??

 

[Bettafanatic]

Did you quarantine the sting Ray? He probably had a contagious disease that all your fish picked up. So sorry all your fish have died. Most people would disagree but I find fish deaths very sad

 

[blert]

How did you acclimate the Ray? Did any bag water get into your tank?

What exactly were the water parameters? LFS "professionals" are not known to be highly reliable. Did they check your water with strips or a proper liquid reagent test kit?

What are your water parameters now?

I believe (not totally sure though) that seizures are normally caused by stress. Was there a lot of stress in the tank after the Ray was added?

Any physical symptoms on the dead fish?

 

[Matt_7689]

Did you quarantine the sting Ray? He probably had a contagious disease that all your fish picked up. So sorry all your fish have died. Most people would disagree but I find fish deaths very sad

I agree! I feel like a bad person. Sounds like he might have picked up the disease from wherever you got him and spread it to your fish.

 

[Andrew McFadden]

I wouldn't rule out a fungus or bacterial infection sometimes it takes awhile before they start to work. Stingrays are very sensitive and should not be kept with fin nippers so the stress alone could have killed the stingray. But sorry for the loss from me hope someone else chimes in here for ya