5 Out Of 6 Cherry Barbs - Dead Within 24 Hours! Help! :(

[NathanS]

Hi all,

I recently added 6 cherry barbs to a newly set up tank - had been cycled, and had water levels tested by the store - all well within acceptable ranges. The fish were doing just fine for the first 4 days, and then suddenly they began to drop like flies... gulping at the surface, and then just...dead. I have one remaining, which is at the surface and showing the same symptoms - and 2 harlequin rasboras, which seem just fine at the bottom of the tank.

What could be causing this?? Should I remove the last cherry barb in case its an infectious disease and affects the newly added rasboras?

Any help would be great

Many thanks

Nathan

 

[Curiosity101]

How exactly did you cycle the tank?

Did the store give you the actual test results in PPM or just say they were 'OK'?

Gasping at the surface IME in a new set-up is normally because of ammonia poisoning. The gills of the fish get chemically burned and so the fish can't get enough oxygen. This causes the gasping.

 

[NathanS]

They bought out the colour charts, and my water resembled the colours (light yellow and light blue) at the lowest point on the chart - thus, seemingly at the lowest possible point. I cycled by adding a source of ammonia, and waiting until the nitrite and ammonia had spiked, and were reading 0. Also, I used tetra's safestart just to boost the bacteria, better to be safe than sorry...

 

[Curiosity101]

What was your source though?

Because if you, for example, cycled the tank with the equivalent of 0.2ppm of ammonia then the tank would be cycled for that level of ammonia. But of course any fish you added would probably create more than that.

When we fishless cycle the reason 5ppm is chosen it to ensure there is more than enough bacteria present to cope with any fish that are put into the tank.