how long do I have while doing a PWC...

[MDDad]

My understanding is that the bacteria in a fully cycled tank reside almost entirely on surfaces - substrate, filter, etc.

However, I've also read that if the bacteria dry out, they die.

If I have to do a 90% PWC at the end of my cycling (to get rid of the nitrates that have built up), that will take a bit of time in a 29G tank...am I in danger of my filter drying out enough to kill the BB during that time?

 

[coralbandit]

No bacteria go dormant before they die...
An article from a rocket scientist I read said he removed his bio media and left it out for 24 hours with no problem...
He did this weekly sometime to do a potassium permanganate treatment on his pool in his basement!!!
Go to this part ; On the day I dose, it is usually my schedule to do the following:
of :
Potassium Permanganate


So the water change is not a problem at all ...

 

[tropical-fish]

I don't see any problem with that. The media wont have enough time to dry out during the water change.

 

[NickNaylor]

I would suggest buying a Python if you have some cash handy. It makes water changes so much less painful. Before, a large water change (80%+) would take me about an hour on my 30-gallon using a 2-gallon bucket, walking it over to the kitchen, conditioning water, etc.. With the Python, I can do a similar water change in about 15 minutes. It's a complete game changer.

As far as the media drying out, I doubt this would be a problem. Moving forward, though, the Python is a worthwhile investment if only because of the time you'll safe.

 

[HooKooDooKu]

If you are concerned with your media drying out during a water change, and if the media can be simply removed, then place some tank water in some sort of container and move the media to the container until you finish your water change.