Transferring One Tank To Another, Instant Cycle?

If you were to “dump” an established 20 gallon tank into a 40 gallon, substrate, decor, filter, water, fish, and all. Would that tank not be cycled? Why do I see so many posts saying if you use an established filter on a new tank, minimum two-three weeks to cycle, yet water does not carry beneficial bacteria? Thank you

 

If you put the filter in the tank, it will work as long as you keep the filter wet/damp.

 

If you were to “dump” an established 20 gallon tank into a 40 gallon, substrate, decor, filter, water, fish, and all. Would that tank not be cycled? Why do I see so many posts saying if you use an established filter on a new tank, minimum two-three weeks to cycle, yet water does not carry beneficial bacteria? Thank you

Could you not add maybe a gallon of new water per day, similar to water change, but just diluting, and keep the cycle?

 

No, water doesn’t carry bacteria. They need a surface with water flow to live there. If you have an established filter, you don’t need to wait 3 weeks, and also, you don’t need to transfer ornaments and gravel either. I just cycled 3 new tanks using only bio media from established tanks.

 

No, water doesn’t carry bacteria. They need a surface with water flow to live there.

This is a fairly common myth, and one that I've regrettably thought was true in the past!

Most species of ammonia-oxidising bacteria (AOB) are motile, and certainly many species of nitrite-oxidising bacteria (NOB) are as well. LI et al. (2018) conducted a study of AOB in the Yellow River (China) and found that they were well represented both in the sediment and in the water column.

I think the myth arose mainly because of earlier research into Nitrosomonas (e.g. Meiklejohn (1950)) where there were issues isolating pure cultures as some strains don't have a motile stage that liberates them into water media.

Now this doesn't mean that using old tank water in a new aquarium will instantaneously cycle it. It might help, but the biofilm of nitrifying bacteria in the filter media is likely to be at a much higher density than in the water column due to the porosity of filter media and their enormous surface area.

 

See, the problem there is a river is very different than a fish tank. The water is flowing, like I pointed out in my first comment, so it would make sense you’d find it everywhere. I should have phrased it better, I didn’t mean the water was completely sterile, there’s bound to be some bacteria in it, but nowhere near enough to cycle a tank.

 

The water is flowing, like I pointed out in my first comment, so it would make sense you’d find it everywhere.

The presence of bacteria in the water column isn't quite related to water flow as much as it's related to the motility of AOB/NOB. That is, they are capable of independent movement via use of metabolic energy regardless of the motion of their surrounding media. Most of the aquarium-based resources (e.g. websites, internet forums) which I've found connects "no beneficial bacteria in water" with the idea that "AOB/NOB are not motile". I think it's a misconception that arose from early research into bacteria culturing.

Most research connects the presence of AOB in particular locations with their motility. As an example, Geets, Boon and Verstraete (2006) wrote: "AOB switch to oxygen-limited autotrophic nitrification and denitrification (OLAND) to produce N2 gas bubbles, which can be used as a means of transport to move out of lake sediment towards a more favourable environment where they can take up oxygen and restart with their ammonia-oxidizing activity."

 

This is a fairly common myth, and one that I've regrettably thought was true in the past!

Most species of ammonia-oxidising bacteria (AOB) are motile, and certainly many species of nitrite-oxidising bacteria (NOB) are as well. LI et al. (2018) conducted a study of AOB in the Yellow River (China) and found that they were well represented both in the sediment and in the water column.

I think the myth arose mainly because of earlier research into Nitrosomonas (e.g. Meiklejohn (1950)) where there were issues isolating pure cultures as some strains don't have a motile stage that liberates them into water media.

Now this doesn't mean that using old tank water in a new aquarium will instantaneously cycle it. It might help, but the biofilm of nitrifying bacteria in the filter media is likely to be at a much higher density than in the water column due to the porosity of filter media and their enormous surface area.

Do you think if I split up a 10 gallon tank with two established filters into two 10 gallons using half the water into one and half into the other then adding new water to both, that they will be cycled?

 

Adding water really does nothing. It is the gravel, plants, and filter pads that keep the tank cycled...As soon as you transfer the filters, transfer the fish and you are good to go.

 

Adding water really does nothing. It is the gravel, plants, and filter pads that keep the tank cycled...As soon as you transfer the filters, transfer the fish and you are good to go.

So, if you put an established filter, substrate, and decor into a new tank with all new water, it’s good to go right away?

 

So, if you put an established filter, substrate, and decor into a new tank with all new water, it’s good to go right away?

yup! If you leave it with no fish in the tank within a day, then your cycle will die off.

This is a fairly common myth, and one that I've regrettably thought was true in the past!

Most species of ammonia-oxidising bacteria (AOB) are motile, and certainly many species of nitrite-oxidising bacteria (NOB) are as well. LI et al. (2018) conducted a study of AOB in the Yellow River (China) and found that they were well represented both in the sediment and in the water column.

I think the myth arose mainly because of earlier research into Nitrosomonas (e.g. Meiklejohn (1950)) where there were issues isolating pure cultures as some strains don't have a motile stage that liberates them into water media.

Now this doesn't mean that using old tank water in a new aquarium will instantaneously cycle it. It might help, but the biofilm of nitrifying bacteria in the filter media is likely to be at a much higher density than in the water column due to the porosity of filter media and their enormous surface area.

Yes, there is bacteria in the water, but like said, not enough to keep a tank cycled.

 

yup! If you leave it with no fish in the tank within a day, then your cycle will die off.

Thank you

 

yup! If you leave it with no fish in the tank within a day, then your cycle will die off.

This is a common misconception: bacteria don't die in 24 hours if they don't have a source of ammonia. They last months/years. I've collected information regarding this and other common cycling myths in another thread.

Do you think if I split up a 10 gallon tank with two established filters into two 10 gallons using half the water into one and half into the other then adding new water to both, that they will be cycled?

It's difficult to generalise, because it depends on the oxidation capacity of the established filter media, how the bacteria will acclimate to the new tank, and several other factors.

I'd recommend testing to be safe: add a dose of 2 ppm ammonia after the new tanks have been filled with established filter media/old tank water, and test in 24 hours to determine if ammonia and nitrite are at 0 ppm.

 

This is a common misconception: bacteria don't die in 24 hours if they don't have a source of ammonia. They last months/years. I've collected information regarding this and other common cycling myths in another thread.



It's difficult to generalise, because it depends on the oxidation capacity of the established filter media, how the bacteria will acclimate to the new tank, and several other factors.

I'd recommend testing to be safe: add a dose of 2 ppm ammonia after the new tanks have been filled with established filter media/old tank water, and test in 24 hours to determine if ammonia and nitrite are at 0 ppm.

If out of water they don't last months.

 

If out of water they don't last months.

This is true! Dehydration affects cell integrity and reduces beneficial bacteria metabolism/growth. But AOBs and NOBs are ubiquitous and they're found in all sorts of areas with very few hydration opportunities (e.g. deserts). They likely undergo some physiological change to protect themselves.

Wood and Sorenson (1998): "To an extent bacteria can overcome the deleterious effects of water stress by osmoregulation, accumulating compatible solutes which protect intracellular metabolic functions from the adverse effects of high levels of internal solutes"

But this doesn't mean you should go wringing out your filter media and hanging it on the clothes line to dry!

 

I like that you’ve researched the topic a lot, I think it’s incredibly interesting. However, I think the results could be significantly different in a man made aquarium. Then you’d have to account for the water differences in each persons tank, on top of the numerous other differences from tank to tank.

I’ve tested the length of time it took for my bacteria to significantly die off without ammonia, while keeping them under water, and after 27 hours it really made a mark on my colony. While it didn’t completely wipe them out, I dosed pure ammonia to 2 ppm, and they got stuck around .25 for two days and nitrites around .50-1.0 for two days. They rebounded after.

OP: if you have an established filter, just use that. Gravel and decorations can be used but are likely unnecessary. The amount of bacteria present in the water, as we would all agree, isn't enough to make a difference.

 

Thank you all!

 

However, I think the results could be significantly different in a man made aquarium.

Absolutely, but peer-reviewed literature allows us to make informed observations based on confirmed hypothesis about natural phenomena. I don't expect our aquariums to align perfectly with controlled experiments, but I would expect the nature and proportionality of relationships between variables to hold.

It's also worth noting that there is quite extensive research literature on nitrifying bacteria and their characteristics in man-made systems such as wastewater management and aquaculture settings (and I've cited examples of these in my other thread). Their primary characteristics (e.g. motility and resistance to deprivation) are the same as those found in natural ecosystems given that they are the same genera and species. Likewise, I've found no literature demonstrating that nitrifying bacteria in aquariums behave in substantially different ways than in other man-made or natural ecosystems.

I’ve tested the length of time it took for my bacteria to significantly die off without ammonia, while keeping them under water, and after 27 hours it really made a mark on my .

I withheld ammonia from my AOB for 6 days when it had begun processing 2 ppm ammonia within 24 hours. After I dosed 2 ppm ammonia, it was oxidised to 0 ppm ammonia within 36 hours, and an immediate subsequent dose of 2 ppm was oxidised within 24 hours. A slight lag, but there wasn't any massive die-off or cycle stall as is often claimed.

I hate to wave the "facts are facts" flag, but a lot of conventional wisdom (not just in this hobby, but many others) seem to be passed and are held uncritically as truth for years/decades at a time. This is probably due to our tendency to implicitly trust the advice of more experienced hobbyists, and our own experimenter bias where we interpret our own experiences as confirmation of our beliefs. I think the Russian proverb is useful: "Trust, but verify."

 

To me, I would think there has to be bacteria in the water since water tests test the ppm IN the water, no?

 

To me, I would think there has to be bacteria in the water since water tests test the ppm IN the water, no?

There are no water tests for beneficial bacteria that I am aware of.....

 

What I watched on YT and read about was to shake off and soak the old filter media in old tank water and pour that into the new tank. It’s gross but the filter will catch it. You could also directly shake or squeeze the filter media in the new tank water. I did this last week and it worked great.

 

Water flows through the filter, where chemicals are then broken down.

 

To me, I would think there has to be bacteria in the water since water tests test the ppm IN the water, no?

The difference is the water tests use a reagent to measure levels of a chemical compound, where bacteria needs a microscopic exam to get a level count.