3 balas dead after med trio

[Phoenix1391]

So i have a community tank that has 6 balas, a gourami, and a pleco. I just did a large water change, thorough gravel cleaning then put in the med trio. I noticed one of the balas had eroded gills, and the 3 older balas seemed to have stunted growth. So decided it would be a good time to medicate the whole tank; as none of the fish have been medicated/quarantine ever(due to ignorance). The day after adding the meds I got home and all 3 of the older balas had passed and the rest were gasping for air. I tested the water with my easy test strips and it showed nitrates between 20-50, nitrites 0, chlorine 0. I also have an air stone going. All other fish were acting erratic and except the gourami. Can anybody give some insight on to what went wrong? We’re the older balas just too weak and should have been treated much earlier?

[Cory]

To actually figure it out, it probably needs some more testing, and info. But in general it sounds like a lot of stress, doing all those things in the same day. What is the temp in the tank? What size is the tank, what size were the fish, what is the current pH in the tank?

[Phoenix1391]

Temp is 78. 75 gallon. The balas were a few years old but only 6 inches. Ph test strips show 8-8.4 ish. Also I noticed the tank was VERY cloudy white, but cleared up today. Rest of fish are acting perfectly normal today.

Edited June 22, 2021 by Adam scharberg

[Colu]

I would test your ammonia levels  the symptoms you describe sound like low levels of desolved oxygen I would add an extra air stone

[Biotope Biologist]

To be technical all your balas and all balas in the aquarium trade experience stunted growth. They can grow to their maximum size in less than 2 years. But yes gasping for air is usually a symptom of ammonia burn. Ammonia is more toxic at higher pH due to their being more free ammonia in the water.

Edited June 22, 2021 by Biotope Biologist