Empty tank ?

[confusedfishmom]

I've got 2 tanks with no fish in them (for about 6 months maybe a year). The tanks have been running but haven't had fish. Water parameters are good. Can I add fish or do I need to cycle it again? The filter media is still in and running. TIA

 

[nirbhao]

Is there anything that would have fed nitrifying bacteria?

 

[confusedfishmom]

Not in my 10g tank. I do have plants in my 20g tank.

 

[SherLar]

It would probably be safer to cycle both tanks again before adding fish.

 

[brendenscott]

I would add 4ppm of ammonia. Then in 24 hours test for ammonia, nitrites, and nitrates. Ammonia and nitrites should be 0. If so then you are good.

 

[Ashenwelt]

I would add 4ppm of ammonia. Then in 24 hours test for ammonia, nitrites, and nitrates. Ammonia and nitrites should be 0. If so then you are good.

Agreed. Know that a new cycle is likely.

 

[toolman]

Very likely, but good luck will be interesting to find out.