fishless cycle without a filter?

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jlk

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Hi everyone! I just got a new (used) 55gal super cheap off of CL. But, i dont have anything yet to set it up (filtration wise) beyond pool filter sand & a powerhead. Have to wait til Christmas! So, my question is- is it possible to cycle a tank without filtration, just oxygenation? I know in theory it is possible but i have never tried it. Any thoughts?
 
I would think it would be much more difficult and/or take a lot longer without the water circulation and oxygenation that a filter provides. I've never heard of anyone cycling without a filter. The nitrifying bacteria needs oxygen as well as food (ammonia and nitrite) to colonize. It is true that the bacteria grows on all surfaces of the tank, but a good chunk of it lives in the filter for this reason.

If your question is whether you could dose ammonia to "start" the cycle right now, I wouldn't see why not. You definitely want to get a filter as soon as possible though.
 
I am just wondering if anyone has ever tried this before. A powerhead & bubblers would provide oxygenation, so i know this is theoretically possible to cycle a tank without a filter as long as its oxygenated. Im not in any rush here so i am thinking i may try to experiment with this tank!
 
Thats what i was thinking as well-to only dose it to 1 or 2ppm and see what happens! I know i can cycle it quickly once i get a filter (tons of established media) but i want to see if this is possible to do because i will give me an idea on how to approach doing a pond this spring.
 
Considering there are some people who choose not to have filters on their tanks, it's got to be a possibility to cycle it without a filter.
 
You could do what I did in my new gf tank. :) Attach a bottle to the bottom of the powerhead and fill it with you media, then when you get your filter transfer it over.
 
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Yes it will cycle, the only difference is that the bacteria colony is not going to be concentrated in one area like the filter media.

The other thing is that it might have more issues establishing a strong biofilter because of lack of space, so to speak.

I have a few tanks that have run on nothing but aeration without a problem, so it can be done, but they are never heavily stocked, or even close to it.

It begs the question, though, if you do happen to have aeration, why not just fashion together a simple sponge filter?
 
Thats Jeta! I may do a simple sponge filter but its probably not absolutely necessary at this point. I am more curious how it will cycle without anything beyond oxygenation & ammonia. I appreciate everyone's input on this experiment!!!
 
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