Seeding new sponge filter without running HOB at the same time?

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Jan 22, 2024
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Hello! I got a new sponge filter for my betta in his 10 gal as he didn’t like the flow of my HOB. I was wondering if there was any way to reliably transfer beneficial bacteria without having to run them both for a month together? I have been doing that, but my little man really doesn’t like the flow and has been avoiding that side of the tank (HOB not adjustable but already baffled, air pump at min setting). Could I for example soak my filter cartridge in a bucket of tank water, and leave my sponge in it for like a day? I was also thinking of cutting the flossy media from the filter cartridge and just wrapping it around my sponge, securing it and running the sponge like that. Would this work?
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I've done the take filter sponge/media out of the HOB and put next to the sponge filter for a while method. Worked fine.
Put your new sponge filter in a bucket with tank water. Run it at full blast and squeeze completely the media from your hob in that bucket let it run an hour and plop it in the tank.

That should kick-start your colony alright. But still, monitor for ammonia and nitrite for a while and perform water changes a needed.
Hello mom. You don't have to run two filters together. Just squeeze out some of the contents of the old filter onto the new one. That's what I've done in the past. You also use a bacteria starter like API's Quick Start to supplement the bacteria in both tanks.

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Rinse out the old media thoroughly in the tank. Don't worry how nasty it makes the water look, the new filer and substrate will take most of it in. That is where the bacteria is living. Running a new filter in the tank with the old one doesn't mean there is more bacteria in the tank. There is only as much as is supported but the amount of ammonia creation.

So at best some of the bacteria will appear to leave the hang-on and move to the sponge. But what wont happen it the total amount of bacteria to increase.

Hold off feeding for the next day or two, The fish will be fine and that will reduce thamount of ammoina being created jik the bacteria is not quite at the level it need to be. It will get there pretty fast though.

If you want to use a bacterial starter product, choose Dr; Tim's One and Only or Tetra's Safe Start. None of the others contain Nitrospira which is what will end up in your tank anyway.

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