Urgent Help Needed

[minimanam]

Tank size:65l
pH:7.5
ammonia: 0
nitrite: 0
nitrate: 25
kH:
gH:
tank temp: 25

Volume and Frequency of water changes:10% per week through gravel cleaning

Chemical Additives or Media in your tank:Water treated before being added every week

Tank inhabitants: 2 zebra Danios and 4 shrimps

Today I have returned to my LFS to get a replacement for the Neon Tetra's that died earlier this week and after acclimatising them as instructed they are beginning to die (2 of 6 dead since putting them in at 3pm - now 7.30pm)

This is the 3rd batch of neons I have tried all with the same consequence!!!

What am I doing wrong

 

[electropunk06]

How long has the tank been set up?
neons need to go into a well established tank (6 months)
hope this helps
Lloyd

 

[minimanam]

Tank has been up and running for 9 months

 

[Harlequins]

Did you acclimatise the neons and for how long?

 

[minimanam]

Did you acclimatise the neons and for how long?

Yeah neons were acclimatised for 30mins by floating the bag in the tank and then over the next 20mins slowly put some tank water in the bag before releasing them into the tank