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How do I maintain a cycled filter w/o fish?

TeaHausCanada

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Joined
14 Jul 2021
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44
Location
Canada
I have an interesting dilema. I have a great little 6.3 gallon long bookshelf nano tank that I set-up about a year ago. It is heavily planted with crypts and various anubias plants. Everything has gone well. Had 4 very small black mollies which have outgrown the size and I just yesterday transfered them into my 36 gallon tank. No livestock left in the nano save 2 amano shrimp and some ramshorn snails. I want to rescape but not straight away. My question is how long can my eheim canister maintain the cycle now that the fish are gone? Do I need to 'feed' filter with ammonia? I'd rather not put any fish in the tank for now but also don't want to tear it down just yet. Any advice/tips are appreciated.
 
Hi
A few members on here, run planted aquariums without any fish!
You will just need to do the odd water change every few weeks to freshen up the water!
The filter will do its job as normal, even with a lower bio load.
Here is mine below!
1664262719097.png

hoggie
 
Hi all,
You will just need to do the odd water change every few weeks to freshen up the water!
The filter will do its job as normal, even with a lower bio load.
What Hoggie says.
Do I need to 'feed' filter with ammonia?
No, the <"whole cycling premise"> isn't really that <"relevant to planted tanks">.

The <"traditional linear view of cycling"> was a best guess based on the <"scientific knowlege at the time">, but <"science has moved"> on and we now know that nitrification is carried out by a network of organisms, if you like it is a London (or Toronto) tube map, not a motorway (freeway) from A to C (or really from NH3 > NO2- > NO3-).
............Before the development of RNA libraries we were reliant on culturing bacteria (from sewage treatment etc) to find out what organisms were involved in nitrification, which led to many of the assumptions about aquarium cycling that we now know to be incorrect. It isn't surprising, if you look at raw sewage it is a very different medium, from even very polluted, aquarium water. There are a number of papers specifically on the nitrifying organisms in aquarium filters which suggest that their assemblage shows a fluid response to varying ammonia loadings, with a stable core of archaea and an ever changing cast of nitrifying bacteria. This is described in <"Freshwater Recirculating Aquaculture System Operations Drive Biofilter Bacterial Community Shifts around a Stable Nitrifying Consortium of Ammonia-Oxidizing Archaea and Comammox Nitrospira">...........
I was pretty sure that the high ammonia, high carbonate hardness <" view of the nitrogen cycle wasn't right">, even before the discovery of all these <"novel ammonia oxidising organisms"> (via DNA techniques), because it didn't make any ecological sense.

To use a <"slightly strange analogy">*, if we only knew about "Polar Bear", we would say that all bears are white, live in the artic and eat an exclusively carnivorous diet, however if we then found "Giant Panda", followed by a "Sun Bear", we could either review our knowledge of bears, or we could carry on insisting that both Pandas and Sun Bears are actually polar, white and carnivorous.

The "all white and carnivorous" argument is really the traditional view of cycling, fine in the past but untenable once we found the other bears, if that makes sense?

* I really like @ElleDee 's <"jam one">

cheers Darrel
 
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If you were concerned what would happen in future if you wanted to add fish again, you could either gradually increase the amount you fed them - what comes out is proportionate to what goes in and/or just transfer a bit of cycled media from your other tank. But a tank with that many actively growing plants, and one that you aren't likely to add a lot of fish due to size those things are probably only really achieving making you feel better about it though :)
 
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