Filter was off for up to 2 days!

[UKSPEED]

Been away for a couple of nights and the filter has stopped, the eheim plug must have come loose from the adapter.
Tank is a 250L housed with South Americans. Been established for around 6 years.

I'm seeing ammonia and nitrite spikes of around 0.5 and 0.25-0.5.
I've just done a large water change.

Fish seem healthy but water was slightly smelly. Power head was still on so some water movement at least. Worried I've lost the cycle, as I've never experienced this before.

Any advice would be welcomed.

 

[fluttermoth]

It's extremely unlikely that all the bacteria will be dead. Keep monitoring the water and doing water changes if needed, of course, but you should soon see an improvement

 

[UKSPEED]

Thanks for the reassurance. That's good to hear!

 

[Byron]

I agree with fluttermoth; in a balanced aquarium there will be more bacteria in the substrate and stoping the filter should pose any problems.

However, with the filter off that long, the nitrifying bacteria will be dead due to oxygen depletion, so the filter should be well rinsed before re-starting. Rinse it under the tap, there is no harm especially since the nitrifiers are dead anyway, though any alive would survive tap rinsing nonetheless.

Byron.