This is a question for people who use/have used a Tetra whisper filter. I just bought a tank kit yesterday which included a Whisper 20 filter.

How often do you replace the bio-bag, if ever?

My thought was to rinse the bio-bag (in tank water) whenever I do a water change, then put in a whole new cartridge every month. Would this sysytem be OK?

I finally fazed out the biobag and replaced it with a big block of biofoam(that traps debri) as it takes a lot longer to get all gunked up I found the biobag was constantly getting mucky and it was very hard not to replace I was having to rinse it alot just to keep it going ..I also suggest eventually to grab another filter as the whispers are ok but not the best .I have the tetra kits and they each have the whisper filters plus another on each.and all is good

I rinse it out every 2 weeks...What type of fish are you placing in there? The whisper 20 pumps 200gph..perfect for goldies

Thanks for the replies! I'm ~eventually~ going to have neon tetras, zebra danios, and cory catfish.

Once I get fish in there, I'll just have to see if rinsing or replacing works better for me.

You could just buy a big bag of filter floss to put around the old biobag frame. It's much cheaper than buying cartridges. And yeah, you can rinse out the biobag and reuse it until it starts to rip. As for me, I'd just buy an aquaclear sponge insert. Just stick the sponge into where the biobag usually goes and make sure it's the right size to make it a snug fit. Then just rinse/wring it out in a bucket of water during water changes.

FYI, according to what I've seen, the Whisper 20 does not pump 200 gph.

Here is my source:
http://www.drsfostersmith.com/product/add_...cfm?pCatId=3643

If there's anything saying otherwise on the Tetra site, I could believe it over Drs F&S, but that's the best info I've found.

Yes, I read on the box of the filter that it only pumps 105 gph..... only enough for 10 gallons.

I won't be fully-stocking the tank for a while yet, so I'll get a second filter/get a bigger filter when the time comes.

Neons, zebras, and tetras are tropical fish, so you're not going to have the waste output that you have with goldies. Their requirements aren't quite as strict except for temps, so you can probably get by with rinsing once or twice a month. I have a Whisper and a Tetra on my 30 gallon tank with goldfish and I've been happy with them.

Rinsing with water changes in fine, and you replace it when its backing up the filter or the flow is noticibly reduced, even soon after rinsing (i.e. I just washed mine this past Sun and it was backing up (water dripping back down near the intake) by Monday, so I replaced it).

My whisper 20 came with some bio-filter-floss so I'd imagine yours would too. That provides extra area for the good bacteria. If you really want to up it you can buy some additional bio media and a mesh bag. Put the media in the mesh back and stick it in the back of the filter.

I used the Whisper 20-40 on my old 20 gallon tank and I just set it up along with my Penguin one on my 50 gallon.....I used to use the bio bags but after a while it seemed like they got clogged really fast. I did rinse them and just change them when they got clogged, but I eventually just quit using them altogether because it seems like they just cost extra money for no reason. But if you are planning on using them, I definitely think it's ok to rinse them and just change them whenever needed.

This is a bit unrelated, but I just realized that I'm using a bio bag for an entirely different purpose. The outflow from my Aquaclear was creating too much of a current, so I jammed a bio bag in at the outflow so the water flows over it and into the tank. It not only diffuses the force of the water, it's also growing beneficial bacteria