Fish Dying

[amyw2008]

I have major problems
436 litre tank, 2 frontosa, 20 small malawis, large plec, 4 jd's & 3 large severums.
Ammonia is 0
Nitrite is 0
Nitrate is 10ppm

Have a filter that does double the size tank & is creating quite a bit of surface movement, also a koralia at the other end to make water move more but fish are gasping at the top of the tank

 

[amyw2008]

Anyone?

 

[Rynofasho]

Planted with CO2? Try a large water change. No matter the problem it's helpful and if oxygen is a problem this would help too. PH stable? Any recent changes to the tank?

 

[ProjectMayhem]

I have major problems
436 litre tank, 2 frontosa, 20 small malawis, large plec, 4 jd's & 3 large severums.
Ammonia is 0
Nitrite is 0
Nitrate is 10ppm

Have a filter that does double the size tank & is creating quite a bit of surface movement, also a koralia at the other end to make water move more but fish are gasping at the top of the tank

Does the surface of the water look grimey or oily? waste and some algaes can sometimes build up on the surface and create a film over the water, this will greatly reduce oxygenation. Solution is a water change and deep clean and skimming off the surface water.