Change all filter media to piece of sponge: good decision?

Hi, can anyone answer a couple of practical questions.

I use two internal filters in my two nano tanks: Tetra EasyCrystal 250 and Dennerle Nano Corner.

1. Tetra has for its filter medium a disposable cartridge with floss pads, activated carbon, bio-filter balls - all in one cartridge. It officially recommends to replace the cartridge with the new one every month. But how about the bacteria? Shouldn't the filter medium be washed?

Or should I throw away the cartridge and replace it completely by the peace of sponge? This is what the seller recommended.

2. Dennerle filter has as the medium some floss pad. It is washable. But, when I asked the seller (different one) about the replacement of filter medium, he also advised to replace it with the piece of sponge. Should I do it? Or should I rather buy the official floss-medium when the time comes to replace it?

Thanks for any insight!

 

the recommendation to change the filter monthly is a money grab so you keep buying filters. i have tanks with filters over 6 months old, i just rinse in old tank water every water change. also, you can cut all that carbon out of your filter so it doesnt rupture when you ring it out in old tank water. all the BB will be on the fabric of the cartridges'. if you do change the filter put a new one in the filter behind the current one for a month to seed it, then remove the old one.

 

Do not replace the cartridge. Rinse it in dechlorinated water/ old tank water in a bucket.

Yes to using a sheet of foam cut to size instead of the cartridge. Again rinse about once every 3 or 4 weeks.

If your tank has a full working nitrogen cycle/ has the bacteria that we call cycled. Leave the old cartridge in the tank on string etc hung in the flow from the filter. Or in a similar place near the sponge in the filter for around 4 plus weeks. Only use aquarium grade sponge. Cut down a block of sponge if need be.

Some models of filters have plastic grid that is stated to be the home for bacteria. Toss that as well and have a large chunk of sponge instead.

edit.
note the sponge is cut just below the overflow. Getting the height just right means when the sponge is totally blocked after months of neglect the water flows over the top of the sponge no over the back of the filter on to the floor.

 

Diy Media Guide For Top Fin Silenstream, Aquaclear And Other Hob Filters | Aquarium Filter Forum | 385506

 

cartridges are wastes of money and are total garbage. switching to sponges is the smart move. just stuff everything you can in there that wont impede your filter

the seller really means "buy more cartridges"