Tropical Fish Forum

Tropical Fish Keeping Help and Advice => Fishtank Filtration and Cycling => Topic started by: Silksheen on June 23, 2014, 04:32:43 PM

Title: Filter Material Replacement
Post by: Silksheen on June 23, 2014, 04:32:43 PM
I have cleaned the white foam type filter in used tank water on the 20% weekly water change. It is now discoloured from my green algae problem which has slowed since leaving the light off. Do you recommend replacing the foam material every so often? Also there is a bag of crystals in the filter housing not sure what these are but do they need to be replaced any time?

I lost 3 Guppy's in as many days a couple of weeks ago. But the other 3 and the 6 Tetras appear to be doing well.

Thank you for your advice. ;)

Mike
Title: Re: Filter Material Replacement
Post by: Sue on June 23, 2014, 04:53:24 PM
Foams (ie sponges) really only need squeezing in old tank water until they fall apart. But if yours have discoloured green and you want to replace it, cut both the old and new into four pieces and replace one portion at monthly intervals.

Brown discolouration is normal.

I don't know what the crystals are. What is the make and model of the filter?
Title: Re: Filter Material Replacement
Post by: Silksheen on June 23, 2014, 06:09:46 PM
Thanks Sue. I could post a picture in the tank pics section to show the filter assy. It doesn't say make or model on it. There are 6 black plastic balls in the first compartment then the foam filter with these bag of crystals compartment, then another compartment with about 6 white cylindrical shaped things.
Title: Re: Filter Material Replacement
Post by: Sue on June 23, 2014, 07:19:49 PM
Is it the filter that came with the tank? Sometimes they don't say what the filter is. In this case, what is the tank?
Title: Re: Filter Material Replacement
Post by: Silksheen on June 24, 2014, 10:06:59 AM
Hi Sue. Here is a link showing the details of my tank. It looks like the bag of carbon crystal's are for removing water anomalies.

http://www.aa-aquarium.com/catalog/product_info.php?products_id=94
Title: Re: Filter Material Replacement
Post by: Sue on June 24, 2014, 11:29:47 AM
Looking at that link, it seems that the filter media includes cartridges made of sponge with carbon inside. If the crystals you mean are black, that's the carbon. You don't actually need it.
Carbon adsorbs chemicals, though not things like ammonia or nitrate. It gets full, and to keep on working has to be replaced. But if you replace the whole cartridge every time it gets full you won't be able to grow any bacteria on the sponge - carbon really needs replacing every couple of weeks.
The simplest thing would be to throw away the carbon and just use the sponge.

The plastic things and the cylindrical things are biomedia, which are the main home for the bacteria. The sponge part of the cartridge is biological and mechanical media - mechanical means it catches the debris.

If you want to replace the foam, I would think about replacing it with plain sponge rather than 'proper' cartridges. Though it is a bit hard to see from the link - is the carbon in a hole inside the sponge or just wrapped in it? If you want to use the proper foam, just throw away the carbon.
Title: Re: Filter Material Replacement
Post by: Silksheen on June 24, 2014, 01:30:10 PM
Thank you for your excellent advice Sue. The carbon is in a small bag and lies in the compartment under the foam filter. As you say it is not necessary to have it, I wonder if the tank may have been configured to use in any type of water quality across Europe and therefore supplied sort of just in case.  It was bought from a department store boxed complete with filter assembly and heater.
Title: Re: Filter Material Replacement
Post by: Sue on June 24, 2014, 02:25:55 PM
Carbon is a hangover from decades ago. Back then fishkeepers rarely did water changes as they thought they were dangerous for the fish. This lack of water changes caused the water to go yellow, and the fishkeepers didn't like that so they used a very simple filter to remove the yellow; basically just a box of carbon with a bit of floss on top to keep the bits out, and an air pump to pull the water through. As the nitrogen cycle became understood modern filters were developed to house bacteria, and the importance of water changes was also recognised. Carbon's only use now is to remove that yellow colour (though with a proper water change routine it should never develop), to remove medication once treatment has finished, and to remove the brown that leaches out of wood. But people get used to doing things a certain way and they still wanted their carbon so the manufacturers continued including it.
Carbon is cheap to make and it needs to be replaced regularly if used on a routine basis. The filter companies make a nice little profit from selling carbon so they won't let on that it isn't necessary.

You can always fill the space with more sponge. Or leave it empty in case you ever do need to use some carbon.
Title: Re: Filter Material Replacement
Post by: Silksheen on June 24, 2014, 03:12:05 PM
Thank you for explaining that Sue. I think I will remove them rather than replace them. At least I now know the reason for the carbon crystals.

Again many thanks. :cheers: Mike.