Tank without fish

[ilaizm]

How long can a tank stay without fish before harming the beneficial bacteria in the filter? Are there any other concerns when keeping a tank without fish?

[rickztahone]

How long can a tank stay without fish before harming the beneficial bacteria in the filter? Are there any other concerns when keeping a tank without fish?

if it's for a prolonged period you will need to feed the bacteria with ammonia to keep the tank cycled.

[ilaizm]

Is 3 to 4 days a prolonged period?

[Jhhnn]

Is 3 to 4 days a prolonged period?

No, not at all. A prolonged period would be weeks.

I wouldn't use ammonia on an established filter, but rather fish food. It'll break down more slowly, serving your purposes better, ime. And it's not like the filter will suddenly die off- the bacterial population will just decrease over time, with the deceased becoming food for the living...