Help Losing Fish And Not Sure Why!

[laurad]

I have a 60l tank which was set up approximately 8 months ago. I happily had 7 neons and 3 xray tetras living in it for a while and had no problems. I added 4 panda corys. I lost one within the first 2 days of them being in the tank but the rest were fine. They were pretty lively. Then I started losing the neons. I now only have 3 left and have recently lost 2 pandas in one day.

For the past few days I have done a 50% water change to make sure that the rest of the fish are ok. The neons appear to be ok, but a bit dull if that makes sense. The remaining cory is fine and the Xrays have never really had a problem.

Should I just keep doing water changes and leave the tank for a while or should I put anything in the water to help the remaining fish out? I know that the tetras and the panda corys prefer to be in groups, so I am a concerned that the panda is by himself and there are only 3 neons but wouldn't like to add more fish into the tank until I know that they will be ok.

Any help would be much appreciated

Laura

 

[JustKia]

While the water changes are good (remember to dechlor your water, and temp and pH match if possible) you need to know what you're acheiving. Do you have a (liquid based) test kit?
Do you know your ammonia, nitrIte and nitrAte levels.
Although the tanks has been running for sometime, something (uneaten food, a dead fish, etc) could have caused a spike in ammonia or nitrItes which could have affected your fish.

Before this incident how often do you do water changes (and how much each time)?
Do you add any chemicals (besides dechlor) to the water?

 

[rdd1952]

What are your water parameters: ammonia, nitrite, nitrate & pH? How long since you added the pandas? Are there any signs of disease on the fish?