australia
Fish Addict
No, i got them from a breeder who has the exacly the same setup! exept they had twice as many fish in the same tank!!!
Just because someonelse does it dont mean its right..., It could be because theres so many fish in there and the water quality is bad....did you cycle your tank?
Whilst I understand you dont have a test kit, I would strongly recommend that you purchase one, whilst a little expensive they are invaluable when it comes to understanding what is happening in your tank and to your fishes. An API master test kit or another liquid test kit.
If you cannot get one immediately, I would take a sample of the tank water to your LFS and ask them to test it for you (some do this free of charge) and get them to write the results down for you.
In the meantime, do a minimum of a 25% water change, if possible angle your outlet from your filter so that it creates more movement, thus creating more oxygen in the water, also if you have an airstone/pump turn it on.
The fish sound like they are in need of more oxygen and/or suffering from ammonia/nitrIte poisoning. The only way to aleviate this is to do regular, sometimes 2/3 times a day water changes of 25% until the levels in the tank get to acceptable levels and your tank cycles.
okay, what do u mean 2/3 time a day? do u mean 2 or 3 times a day do 25%?

You're welcome!! Let us know how it turns out!!