gunk in filter sponge

[romanjetfighter]

i have a HOB filter with a spongey insert and found after 3 months it was clogged and water did not go through it anymore
i forgot i had to wash it in water and when i did, a lot of crap came out of the filter
it smells like soil or foresty dirt floor and i was wondering... what is it?

can i use this to seed my other filters, or is it just crap like nitrates and stuff?

 

[Inglorious]

That would be uneaten food, fish poop, and other stuff like that. You actually don't want that gunk in your filters because it breaks down into nitrate eventually so if you can remove it before then it keeps your water parameters in better condition. If you have any small plants it will make good fertilizer though, but most people just rinse it off in the sink and let it go down the drain.

 

[duanes]

By cleaning the sponge out regularly you increase the efficiency of your filter, and keep nitrates down.
Once or more per week is not too much, I find squeezing it out in water from a water change each time is a good routine.
Allowing it to gunk up is kind of like not flushing your toilet.

 

[HeatherE]

So would I want to squeeze them clean? Like it doesn't have carbon or anything special that I don't want to squeeze out?

 

[Inglorious]

Squeezing them in the old tank water you're removing during a water change is probably the best way to clean the sponges because it will preserve most of the bacteria you need to keep your tank cycled, but you can clean them in running water for a more thourough cleaning. If you do that though, you need to make sure you have enough biological media that your tank won't go through a mini cycle. The sponges should be acting mostly as a mechanical filtration to collect all that gunk, but the good bacteria will grow in them as well, so you should try to avoid losing it as much as you can. And no there shouldn't be any carbon or other chemicals in there that you need to worry about losing. You can buy special sponges that have chemical properties, but it is very unlikely you have them since you need to go out of your way to buy them.