Seeding sponge filters in an established tank

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IHaveADogToo

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I have an established 30 gallon tank that has a standard Hang-On-Back filter. I used to run an air stone in this tank, but I have since opted for secondary filtration, and now I use a sponge filter *instead of* an air stone. They both bubble and oxygenate the water, so why not? It's additional filtration, in addition to oxygenation.

Question:
After running this sponge as a secondary filter for several days or a week, or whatever amount of time it takes for the bacteria colony to latch-on to the sponge, would moving it to a new tank help the new tank cycle faster? (I've had this sponge in there for 2 weeks, and I'm thinking about stealing it for a new tank, and replacing it with a new one in the established tank)

Have I just discovered a way to seed sponge filters and make new tanks cycle faster? Or does moving the sponge filter to a new tank with new substrate and new plants/decor kill it's bacteria colony?
 
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Its not a new way but most people reckon 2 months to be safe. A lot of people keep a sponge filter in their main tank so when they need a hospital or quarantine tank they move the sponge filter over for an instantly cycled tank.
 
Its not a new way

It's new to me!

So if I let this sponge run in the main tank for another few weeks it'll probably be good to start another tank with? And then I can start seeding another?

So happy I discovered sponge filters :)
 
Just remember your filters (combined) only contain as much bacteria as is needed for the tank. So when you take it out you should test both tanks. Not really an issue because in an established filter the bacteria can double in 24 hours - but you should be aware. You don't get extra BB - its just shared between the 2 filters.
 
*I will not be taking a sponge from this tank at this time, as I just discovered ich in the tank.

I've started a new thread for that.
 
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Have I just discovered a way to seed sponge filters and make new tanks cycle faster? Or does moving the sponge filter to a new tank with new substrate and new plants/decor kill it's bacteria colony?
No you didn't discover anything new, sorry :)

As Seangee said a lot of people do it. I use Aquaclear HOB filters and have 3 sponges in them. If I ever want to set up a new tank I take one of the sponges from an established tank and put it on the new tank. Instant cycled filter. Obviously by moving only one of the filter sponges I am only taking 1/3 of the filter bacteria, but that is sufficient to get a new tank going and the bacteria multiply rapidly, usually doubling their numbers every day.

Filter sponges should be at least 1 month but preferably 2 months old before using in another tank.
 
A good alternative is to attach the sponge filter without airpump (or even just the sponge) to the intake for your main filter. That way you always have a "ready to go" sponge filter and you get to spend less time cleaning the main filter because the solids are pre-filtered out of it :)
 
A good alternative is to attach the sponge filter without airpump (or even just the sponge) to the intake for your main filter. That way you always have a "ready to go" sponge filter and you get to spend less time cleaning the main filter because the solids are pre-filtered out of it :)

Yes, I actually just saw a video on that from one of the youtube aquarists. He put several sponges inside an external canister filter, but explained you could put them on the intake of a HOB. I might give that a go, too! Water sprite tends to get stuck on the intake, so I've been considering putting a sponge over it.
 
Make a loop/ circle of airline or plastic hose and join the two ends together with an airline joiner or polypipe connector. Then Stick a couple of suction cups to the glass at the opposite side of the aquarium and tie the plastic tube/ loop/ circle to the suction cups. Have the string about 6 inches long. Then put the water sprite inside the circle. The plastic airline will stop the plants being pulled down to the intake tube. And the string will allow the plastic circle to drop down a bit during water changes and keep the plants trapped in the circle.
 
I like that!

Yeah, the problem seems to be that whatever is on top of the water just naturally gets drawn towards the filter output. So floating plants are always drifting into the waterfall, and getting pushed under, where the filter intake catches them.

I do have some spare airline tube... I love ingenuitive ideas like that!
 
A good alternative is to attach the sponge filter without airpump (or even just the sponge) to the intake for your main filter.
Hmmm - thought about this today while rinsing my "pre-filter" sponges.

So if the sponge filter is cycled does this mean that it deals with all the ammonia encountered before it reaches the cannister filter? And if that is the case does it mean that the cannister has actually become uncycled due to lack of ammonia for the BB in there?

Not really an issue in my case as the tank in question has 2 cannisters and only one has a "pre-filter" (i.e. simple sponge filter stuck onto the inlet hose), and I have plenty of plants. Just wondering if this approach has the ability to crash the tank if you were to remove the sponge filter to set up a hospital tank or QT :dunno:
 
So if the sponge filter is cycled does this mean that it deals with all the ammonia encountered before it reaches the cannister filter? And if that is the case does it mean that the cannister has actually become uncycled due to lack of ammonia for the BB in there?

Doesn't the beneficial bacteria live everywhere in the tank, though? Not just on the filter media?
 
Correct. But usually the largest accumulation of the nitrifying bacteria (or probably archaea) will reside in the filter simply because the continual water movement is bringing ammonia into that space. Bacteria/archaea will multiply by binary division so long as there is ammonia, but once the bacteria/archaea are in sufficient numbers to handle the ammonia, multiplication will cease. Should the ammonia then decline from that level, the bacteria has the ability to go into a sort of suspended animation or hibernation. It can remain in this state for some time, depending upon other factors. Nitrifying bacteria will also live in the substrate, and on most any surface under the water.

So if the sponge filter is cycled does this mean that it deals with all the ammonia encountered before it reaches the cannister filter? And if that is the case does it mean that the cannister has actually become uncycled due to lack of ammonia for the BB in there?

I do not know the answer to the first question in this quote. But as explained above, the bacteria in the canister filter are unlikely to die. However, the accumulation of denitrifying bacteria can smother them, which is why you should keep the canister clean. The brown gunk is organic matter, and this is what the denitrifying bacteria feed on.

You mentioned plants...studies have shown that plants that are fast growing species will take up ammonia/ammonium quicker than the nitrifying bacteria. This is why live plants, especially floating which are fast growers, will "silent cycle" an aquarium without harm to the fish. The benefit of plants is that they not only take up ammonia/ammonium rapidly, but they do not produce nitrite as a result, so the nitrite is a non-issue for fish. These bacteria will still establish, but more slowly. Eventually you may or may not ever see nitrate, depending upon the fish load, plant load, and organics. In low-tech method or natural planted tanks with lots of plants and many fast growers, that are not too heavily stocked with fish, nitrate can remain at zero, which is ideal for fish. My tanks run in the 0 to 5 ppm range for nitrate because I tend to have a lot of fish.
 
Duckweed is one of the best floating plants around for cleaning water, If your duckweed is growing fast it means there are lots of nutrients in the water.

I never see nitrates in my tanks, While this is not everybody's cup of tea, this is the best filter money can buy.
CFueSFO.jpg
 

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