My clownfish died with heavy breathing

[jgenovana]

So I bought am adult clownfish 2 days ago from LFS, along with 4 blue yellow tailed damsels, a dotty purpleback and a cleaner shrimp. My tank has finished cycling using NSW after all params has been okay. I bought one small test clownfish which lived a week before I bought these livestock 2 days ago. But today, my adult clownfish died. The only thing I noticed is heavy breathing, and it only was on one side of the tank. The small clownfish however just swam beside it, healthy and happy. What do you think caused it to die? Poor aeration? I only had one 5 watt pump for the water movement. I havent bought a wavemaker. Anyway, all other fish I bought alongside with the adult clownfish are pretty much alive and healthy.

 

[Crabs McJones]

Welcome to R2R and sorry for your loss. Can you provide us with your parameters, tank size, and pictures? It's possible that by adding that many fish at once it caused a nutrient spike.

#WelcometoR2R

So I bought am adult clownfish 2 days ago from LFS, along with 4 blue yellow tailed damsels, a dotty purpleback and a cleaner shrimp. My tank has finished cycling using NSW after all params has been okay. I bought one small test clownfish which lived a week before I bought these livestock 2 days ago. But today, my adult clownfish died. The only thing I noticed is heavy breathing, and it only was on one side of the tank. The small clownfish however just swam beside it, healthy and happy. What do you think caused it to die? Poor aeration? I only had one 5 watt pump for the water movement. I havent bought a wavemaker. Anyway, all other fish I bought alongside with the adult clownfish are pretty much alive and healthy.

 

[FindingNem0]

Adding fish to suddenly which caused an ammonia spike or did not acclimate the fish.