Just A Sponge In A Filter?

[jvdb]

I have decided to revisit my childhood aquarium hobby and this time do things with proper research  I am up to date on aquarium cycling and well aware of how crucial it is for an aquarium to have healthy bacteria, so now my question comes to filtering.  My tank is FRESHWATER.
 
I terms of filtering my goal is to:
1) Remove debris - which I assume will be minimal due to the fact that I have a fish only tank.
2) Maintain a balanced system with healthy bacteria - which grows on the filter medium correct?
 
Now when it comes to choosing filter media I am a bit confused.  Have read a few articles and am wondering why all the "extras" are necessary.  Why would I need carbon if I keep up with my water changes (say weekly?).  Shouldn't simply pumping the water through a sponge be enough to catch debris and allow exposure to the bacteria growing on the sponge?  Am I missing something?
 
Also if my reasoning is correct, how often should I clean the sponge and how?  My thoughts are to clean every second week or so by simply squeezing it out and removing the debris in OLD aquarium water.  My logic for this is that the debris needs to be removed but I hope not to kill or remove the bacteria in the process.
 
Is this reasoning correct or am I missing a large chunk of the equation? Any corrections in my thinking or tips are greatly appreciated!

 

[TwoTankAmin]

Well, how much bacteria may be in one's filter vs everywhere else in a tank is nowhere near a fixed issue, despite what you may read on this and many other sites. Basically, a tank will develop the needed bacteria which will live where ever it must/can. In a properly set up tank which is also maintained properly, the filter should offer the most hospitable location for much of the non-free floating bacteria. The create a protective bio-film which attached them to hard surfaces. So they do not go looking for what they need, instead it must be delivered via water flow. If a filter is not large enough or if it is allowed to clog, then the bacteria will be found elsewhere in a tank.
 
The next most common place bacteria will colonize is one's substrate. In tanks which do not have live plants in the substrate, the bacteria will only be found in the top half inch or so as below that depth there is little of no oxygen which the bacteria need, In a planted tank the substrate is alive with bacteria almost to the very bottom glass. This includes anaerobic areas where denitrifying bacteria will live. Moreover, bacteria will colonize almost any solid surface where there is OK flow to deliver what they need.
 
Sponges are tried and test filters. As you noted they provide a home for the bacteria and also trap waste. But they offer no good method for holding chemical media. While many folks only use carbon to remove things such as medications or perhaps staining, they have a place to put in their filter if needed. Moreover, sponges can trap only so much in terms of particle size. So many folks want a better mechanical media such as filter floss. For these things a free standing sponge offers no help. But many people, myself included, use sponges as some of the mechanical and the biomedia in our power filters and canisters.
 
it is possible to hang a mesh bag holding carbon or other treatments near the sponge or over the top of the uplift tube, but this is less efficient than having it in a filter. If one doesn't want to do this and also does not want to run a power filter all the time I would suggest getting a small hang on which is only used when you must run carbon, or crushed coral or similar chemical media. You use it when needed and store it when not.
 
The last thing I will suggest is a superior foam. It is superior to the typical sponges we normally use in the hobby and is available in a variety of colors and porosities (specified as PPI- pores per inch). It is called Poret Foam (from Europe) and can only be purchased from this site http/www.swisstropicals.com/filtration-shop/poret-foam-shop/  I use some in a few of my tanks.
 
To clean standard sponges or the Poret, the idea is not to squeeze them really hard but rather to swish them in a bucket of either tank or dechlored tap water. You can tap them against the side of the bucket to help dislodge things. I have found the Porets to work great and if I am behind on maint. work I may have to double rinse them by using a second bucket of water to get them clean.
 
Lastly, clean your filter media weekly in most tanks, especially if using only sponges. The more they clog the more at risk the bacteria are of being suffocated. But when it comes to changing water and rinsing filter media properly, it is better to do it a bit too often than a bit too infrequently.

 

[jvdb]

Thank you Twotankamin, that was very helpful!  I am realizing that while a simple sponge filter (which I think I will DIY) will be effective but will require regular gragel vaccuming which is easy enough.

 

[b3cca]

Also you could consider buying a cheap roll of filter floss to put on top of the sponge which will remove the larger/dirty particles before they reach clog the sponge meaning far less sponge cleaning.
 
I have floss as a pre filter and just change that every week I think I've actually cleaned my sponges twice in the past year