Keeping The Biological Filter Alive

[fishboytoo]

I was just wondering how long the bacteria will remain alive in the absence of ammonia. How long does it take them to starve?

I was just wondering because I'm going to be adding fish to my newly cycled tank but I will be doing a 95% water change first. How long will I have to add the fish before the filter is damaged. I suspect it is atleast 24 hours. Anybody have the precise amount of time?

 

[Rooster]

Would NOT like to leave it longer than a couple of hours.... just feed it a little ammonia to keep them happy...

 

[Tempestuousfury]

Why are you doing such a large water change?

Add some food and old tank water, and it should last long enough, I would think. *speculation*

 

[carrera]

Why are you doing such a large water change?

Add some food and old tank water, and it should last long enough, I would think. *speculation*

i thought a large water change was called for at the end of a fishless cycle

 

[TammyLiz]

Yeah, you're on the right track. Change the water just before you go to the store to get the fish. I have heard the bacteria can significantly die off within a day. I would think that even if you changed it in the morning and got the fish in the afternoon it would be OK. Just try for as close to it as possible. You can't do any better than that.

 

[fishboytoo]

Thanks for replying.

I am doing the large water change because my nitrates are so far off the scale it's silly. Even leaving 5% of the water will probably result in high nitrate levels. I've been dosing large amounts of ammonia because this is going to be a cichlid tank and I will be adding a large amount of bigger fish right off the start, so I wanted the filter to have a large capacity.

I've only been dosing once a day and the bacteria haven't died off, hence my reasoning on the roughly 24 hour period before starvation.

I will try to get the water change and new fish as close together as possible. I was just wondering if anyone knew if there was a precise amount of time.

 

[IovaykInD]

There's no such thing as precise time with fishkeeping

I'd say it'd be different for different sized filters, the larger, the longer it would last without fish.

 

[TammyLiz]

Seeing as you've been dosing such high levels of ammonia it'll probably be fine even if you do it the day before adding the fish. If you've got so much surplus bacteria it won't even matter if a lot of it dies off. In any case, it'll take a while before it completely goes. Once I left a tank sit empty but with old water for a week. I did a water change and gravel vac and added what amounted to 20% stock with no ammonia spike. This hints to me that its probably able to survive on much less waste than we think. In that tank it was probably consuming whatever waste was rotting in the gravel....so it could be that your totally empty tank will not have the same results.

Tammy

 

[Tolak]

Fish will survive bagged longer than you think. I buy & sell fish at swaps that are bagged at room temperature for over 12 hours, they do just fine.

That being said, once the tank is fully cycled, go buy the fish you want. Keep them in the bags in a cooler to retain temperature. If your nitrate are insanely high, let's say 500ppm, doing a 90% w.c will bring them down to 50ppm. Doing a second change of 90% will bring them down to 5ppm. While you are doing these multiple water changes your new fish are kicking back in the nice dark cooler. Once you are done with water changes acclimate the fish using whatever procedure you prefer.