Fish are dying can someone help?

I bought some new fish from dobbies garden centre on saturday (got 3 Endler Guppies Still alive, 2 Guppies Died )and since then they have died and also 2 of my other established fish have died aswell, I have checked everything, my PH 7.0 Ammonia is 0 Nitrate 10, Nitrite is 0.3. Yet they are still dying, Im running a fluval Uno 600 63litre tank with a fluval 2plus internal filter, I have done a water change of 40% and test the water after it and the levels are perfect. could someone help me.

The fish that have died have been Red Glo-lite Tetra, a cory and also 2 guppies.

Fish are dying can someone help?
That is very strange. Try calling your local pet store, I have bad luck with fish!
Reply:Sounds like you got a hold of some sick fish and then spread it to your established fish.

Always QUARANTINE new fish. Saves you established fish.
Reply:Did you let the sealed bag float in your tank water for about 15 to 20 minutes so that the water in your tank adjust the water in the bag? If not, it's possible you could have stressed the fish which could have lead to them dying.



Did you add and water conditioner to the water after you added the fish? You are suppose to! It reduces stress if any occur after adding.



If your water reading are good like you said and you did all that I just asked when you fist got your fish then the only thing it is is that you got yourself a bad batch of fish and should try taking them back to where you brought them from to get them replaced if possible or a store credit for the death of them.

acne scars