my fish died

Ok so i put 2 mollies in my tank last night. I was told that they will survive in both saltwater and fresh water so i put them in my tank. I tested the water before i did so and everything looked good. When i woke up this morning both fish were dead, i tested the water again and my lvels were as follows. Nitrate 20: nitrite .5: alk 300: and ph 8.4: is this ok or did i do something wrong?

 

Mollies have to be acclimated veeeeery slowly to salt water if they've just come out of a freshwater tank. Some pet stores sell mollies that have already been acclimated to salt water but I have a feeling that this was not the case in your situation.

 

hmmm as in add salt water to the bag slowly before etting them into the tank or what???

 

Yes, you have to add salt water from your tank to the bag that their in very slowly before putting them into the tank. I drip acclimate them for several hours myself just to play it safe.

 

thank you very much for your help