Changing filter media

[davidmold]

I have a Whisper filter, which has a standard cartridge. I'd like to change it for one of their bio bags that has a sponge and other stuff in it. But if I change it, will I lose all my ammonia and nitrite-eating bacteria I am just so carefully cultivating? Or will it be okay?

 

[CAPSLOCK]

You won't lose all the bacteria, since there is some in the gravel, decorations, walls, filter itself, etc. But you will lose a good portion. Can you stick in the new cartridge at the same time for a few days or a week, so that the bacteria have a chance to populate both? That way there will be less of a jump. Or, you could swirl the used cartridge around in the tank so most of the bacteria goes into the water and then can settle onto the sponge cartridge.

 

[davidmold]

Thank you, that helps. I think I will try running the old cartridge with the sponge from the new one in front of it for a day or two.

In the book I read about maintaining aquariums, it suggested the bacteria colonies were really quite difficult to dislodge, and that swirling the cartridge in the tank would not have this effect. Given that water flushes through the cartridge all the time, it seems to me unlikely that they could be dislodged in this way. But I am certainly no expert so I am probably wrong.

This must be a problem for everyone who uses these filters. On the Tetra website, Q & A they say you should not re-use the cartridges but replace them once a month, but don't address the issue of what happens to the bacteria.

 

[rohnds]

Place the bio bag anuwhere in the tank and let it cultivate the new nitrying bacteria. It will take about 4 to six weeks. In another word you are cycling a new filter. Once the bio bag has devloped you can safely removed the old filter media.

By simply placing the bio bag next to your old filter doesn't guarantine that the bacteria will simply "leave" old filter media and colonize the new one. It take time.

Rohn

 

[jefftaylor]

Place the bio bag anuwhere in the tank and let it cultivate the new nitrying bacteria. It will take about 4 to six weeks. In another word you are cycling a new filter. Once the bio bag has devloped you can safely removed the old filter media.

By simply placing the bio bag next to your old filter doesn't guarantine that the bacteria will simply "leave" old filter media and colonize the new one. It take time.

Rohn

I tend to disagree with the last statement. if you have one media sponge next to the other what goes in must come out so it has to and will go through the new sponge. So i think by putting the sponge in the filter itself over just putting it in the tank will have more of a beneficial presence.

 

[davidmold]

Yes, jeff, what you say makes sense to me - although bacteria would no doubt colonise the sponge in the tank, much more water, and therefore bacteria, should flow through it in the filter.

It would be great if there was an easy way to tell if the bacteria were actually growing on the sponge. I suppose I could put it in a bucket with some ammonia in the water... any thoughts?

 

[Lotus]

If you're still cycling, I recommend you don't change the filter cartridge until the cycle is finished.

You can put both of the sponges in there for a few weeks, then take out the old one when the cycle is finished (I think you're cycling, from your other posts).

 

[davidmold]

Yes, Lotus, that's right - I won't change the bag until it's finished cycling.

Here's the response I got from the people at Tetra:

You will have most of your good bacteria in the gravel, fake plants,
ornaments, etc. If you have the filter with the bio-foam, that will have
much more than the filter bag itself. You can re-use the frame to keep
some of the bacteria.