Help Needed fish dropping like flies!

[chriscarter2525]

Hi urgent help needed, I have a juwel rio 180 vision and my fish are dropping dead one by one without any reason.

THe tank is 6 months old so it is fully cycled:

Amonia, Nitrate, Nitrite are all zero PH is 7 so water is spot on as I do weekly water changes of around 25%. I have a large airstone around 8" so there is plenty of oxygen in the tank.

Fish are as follows:

7 x Guppies
7 x Neon Tetra
1 x Harlequin
2 x Mollies
1 x Plec (2")
5 x Platy Fry

The guppies tail are starting to fold over and they are gasping at the surface! There are no signs of parasites or slime desease etc? I have added aquarium salt but this morning I lost my last platy and a guppy!

Any ideas would be appreciated?

Thanks Chris

 

[Rbishop]

I would be uncomfortable with a reading of zero on nitrates unless it is an extremely heavily planted tank, even if lightly loaded. What kind of test kit are you using, a liquid one? Current tank temperature? I don't think you need the salt, but was it very well dissolved when you added it?

 

[chriscarter2525]

Tank temp is 24 degrees. I have quite a few plants in the aquarium mainly amazon sword all seem to be doing fine. I used a liquid test kit and carried out the tests twice all are zero! The salt is all disolved.