Mass Death

[Anastasia]

Hey
recently upgraded my tank from 40litres to a 150 litre tank, after setting up my new tank i transefereed my fish guppies, fighting fish, neon tetras, swordtail and platies, and 2 brislte nose catfisha few days after setting up my tank all of my guppies, tetars and platies(platies were brought new for tank). can anyone help me with what could be the cause i never had any problems with dying fish in my smaller tank. also a swrod tail is just stting on the bottom of my tank and not swimming. please help

 

[Tolak]

How did you cycle the new tank, or did you transfer the filter media from the old tank to the new one? Posting results of water tests will help to figure out if it's a water problem. If you don't have a test kit most lfs will test your water for you. If this is the case, have them write down the numbers & post them here.