“Cycling” extra media by setting at bottom of tank.

MoshJosh

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Basically wanting to know if media can grow bacteria efficiently when simply sitting on the bottom. I know we do this in filters and sumps but without direct water flow will the media still cycle, will it just take longer, or does it matter at all?

Also do things like Turbo start and seed negate the need for cycles media or more of a supplement? I’ve used seed and seems to work great, however, I haven’t done any actual tests to see the difference personally (especially when starting a new tank from scratch).
 

FinalFins

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I have tons of extra media at the bottom of my 2.5 tank. seems to work alright. But obviously running water past it helps.
 

86 ssinit

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It will grow but yes it will take much longer. What you could do is take some media out of the filter and let it sit on the bottom of the tank. Than add the new media to what’s left of the old. This way the stuff sitting on the bottom is still alive and the new stuff is being seeded by the old.
 

Momgoose56

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Media won't seed "efficiently" sitting on the bottom of the tank. Some bacteria will grow on it over a few months but only as much as what grows on your substrate and anything else sitting at the bottom of the tank. The most efficient way to seed new, extra media is to put it in the overflow chamber of a HOB filter or a basket in a canister filter. If I want to seed new media, I add extra into my canister baskets or hang an extra HOB on a tank, cram it full of ceramic biomedia and let it run for a month.
 

oldsalt777

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MoshJosh said:
Basically wanting to know if media can grow bacteria efficiently when simply sitting on the bottom. I know we do this in filters and sumps but without direct water flow will the media still cycle, will it just take longer, or does it matter at all?

Also do things like Turbo start and seed negate the need for cycles media or more of a supplement? I’ve used seed and seems to work great, however, I haven’t done any actual tests to see the difference personally (especially when starting a new tank from scratch).
Hello MJ...

Bacteria will grow on any surface in the tank. It simply needs oxygen and a food source. Bacteria grows as soon as there's oxygen and ammonia. You don't need any chemicals other than the standard water treatment to start a tank. You need a source of ammonia by adding a few small fish and feeding them. You add some floating plants and change a third of the tank water every three days for the first two weeks. Then, you change half the water weekly for the life of the tank. That's it.

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Sorg67

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oldsalt777 said:
Hello MJ...

Bacteria will grow on any surface in the tank. It simply needs oxygen and a food source. Bacteria grows as soon as there's oxygen and ammonia. You don't need any chemicals other than the standard water treatment to start a tank. You need a source of ammonia by adding a few small fish and feeding them. You add some floating plants and change a third of the tank water every three days for the first two weeks. Then, you change half the water weekly for the life of the tank. That's it.

Old
This sounds reasonable to me.

But why do people say "fish-in" cycling is so hard on the fish? It seems that if you test your water every day and do enough water changes to keep ammonia and nitrites down to 0.25 or less, it should not be too rough on fish.

Especially if you treat with Prime or similar to detoxify the small ammonia and nitrite concentrations.

Is the problem with fish in cycling mostly that people do not stay on top of the water changes?

Fishless is easier since you do not have to do as many water changes?
 

mattgirl

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Sorg67 said:
This sounds reasonable to me.

But why do people say "fish-in" cycling is so hard on the fish? It seems that if you test your water every day and do enough water changes to keep ammonia and nitrites down to 0.25 or less, it should not be too rough on fish.

Especially if you treat with Prime or similar to detoxify the small ammonia and nitrite concentrations.

Is the problem with fish in cycling mostly that people do not stay on top of the water changes?

Fishless is easier since you do not have to do as many water changes?
Before bottle bacteria's became so popular this is how it was done. This is still the way I do it. If done right no lives are in danger. It does take a bit more work though as far as water changes go.

This isn't very popular here on the forum but I feel one gets a stronger more natural cycle by doing a fish in cycle. I think, but of course can't prove, that there is more to the ammonia that fish and the food they eat produce than what is in bottled ammonia. One can cycle with bottled ammonia and bottled bacteria but I feel the cycle is more delicate for a longer period of time and can be lost easier.

as always just my personal opinion. :)

and to answer the original question. I think as long as the media has water flowing over and through it, bacteria will grow on it .
 

oldsalt777

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Hello...

Cycling a tank with fish is fast, simple and doesn't hurt the fish at all. You do need to select a hardy fish species and once the fish are in, you have to pay fairly close attention to the water. However, if you feed the fish a little every day and remove and replace a third of the water every three to four days for the first couple of weeks, you'll remove the toxins before they build up and cause problems for the fish. You really don't have to test the water. After the initial two weeks, you start changing half the water weekly for as long as you keep the tank. It's that easy. If you decide you want a few more fish, you can. Simply add the fish slowly and increase the amount of the weekly water change.

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Momgoose56

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Sorg67 said:
This sounds reasonable to me.

But why do people say "fish-in" cycling is so hard on the fish? It seems that if you test your water every day and do enough water changes to keep ammonia and nitrites down to 0.25 or less, it should not be too rough on fish.

Especially if you treat with Prime or similar to detoxify the small ammonia and nitrite concentrations.

Is the problem with fish in cycling mostly that people do not stay on top of the water changes?

Fishless is easier since you do not have to do as many water changes?
There are a few problems with "fish-in" cycling. When a tank is cycling, there are daily/hourly changes in pH and other parameters as the cycle progresses. A chemical/biological maelstrom is going on in the tank. No amount of water changing will prevent this. No amount of Prime will ameliorate many of the chemical changes. Even if you can keep fish alive and healthy looking, a tank going through the cycling process is an incredible stressor for fish. Second, it just takes longer. Some people claim they've fully cycled a tank in two weeks just with fish in it. Doubtful. It takes an average of 20 hours for nitrifying bacteria to replicate. Nitrosomonas and nitrobacter are among the slowest growing bacteria there are. In the time it takes these bacteria to make a single copy of themselves, other bacteria (like some of those that cause disease/infection) have made billions of copies of themselves. In addition, the speed that nitrifying bacteria will replicate is highly dependant on the inherent characteristics of the water surrounding it. These characteristics include pH, temperature, general hardness of the water etc. When doing a fish-in cycle, you don't have the freedom to adjust these parameters drastically to fit the needs of the bacteria you are trying to grow. For instance, say your pH is 6.0. That is a pH that none of the nitrifying bacteria will replicate in. Without fish, you can raise that pH to 7.5 with a buffer instantly and maintain it throughout the cycle, then let it drop back to it's natural level before adding fish. Even raising the pH that much slowly, with fish in a tank, would likely end up eventually killing some and causing permanent problems for others.
So, that's a very limitedbasic rough idea of why fishless cycling is easier, generally faster, and more efficient than trying to cycle while keeping fish healthy in a tank.
 

oldsalt777

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Hi Mom...

Whoa! This is a lot to wrap my brain around. Many years ago, when I set up my first tank, I didn't think about the science stuff at all. I wanted some fish right away. I set up the tank with all the gear, filled it and added some floating plants. I let the tank sit for a day or two and put in some Guppies. I fed them a little every day and changed out some of the water a couple of times a week. After a couple of weeks, I added some more small fish and started removing and replacing half the water every week. I had fry after a month or so. Over quite a few years, I've used this means of setting up a tank many times and with many different fish. This system is so simple and you get to enjoy fish almost immediately. You really don't need to know anything about the water chemistry. You just need to commit to an aggressive water change routine.

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Sorg67

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Both arguments seem plausible. I guess you would need a team of microbiologists, biochemists, ichthyologists and a few hundred fish tanks to run experiments of a variety of fish species to get to some definitive answers.

Intuitively @mattgirl 's argument that a fish-in cycle results in a stronger more balanced cycle makes sense to me.

And @oldsalt777 's argument that it you stay on top of water changes you are probably not doing a lot of damage.

@Momgoose56 's argument that there is a lot of water chemistry going on in a cycle that does not show up in ammonia and nitrite monitoring seems plausible. And it would seem that the fishless cycle would achieve the same stability as fish-in over time. Although it also seems plausible that some of the other water chemistry gyrations could happen as the fishless cycle stabilizes.

I appreciate you all taking the time to explain your rationales. Very educational - apologies to OP for the digression. Hope this was helpful to you too.

Regarding OP's question about stuff sitting on the bottom, I wonder about that too when people talk about leaving a non-bubbling sponge filter on the bottom as instant cycle material. I seems like that would give you a headstart, but not an instant cycle.

Part of the appeal of this hobby is learning about all this stuff.
 

oldsalt777

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Hello again...

The large, weekly water change is all you need to maintain a healthy tank. The more aggressive the change, the better. You don't need to know anything else about the hobby other than this. I've always kept the hobby very simple, so I've been able to keep several, very large tanks with a lot of fish with just a little work. As I close in on retirement from the workforce, I can keep even more tanks and just spend time changing water and admiring all my fish.

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86 ssinit

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My 2 cents :). The fishless cycle. I’ve never done it. I understand it and I think it’s great for a beginner. It’s teaches you patience!! Now the fishless cycle has changed. It’s now being done with bottled bacteria and is happening much faster than when it was done without.

The fish in cycle is how fish tanks were done from the beginning. As old said we used guppies,feeder goldfish or any strong fish back than. I never had a problem doing it this way. Usually gave the starter fish back to the store for store credit.

Now once your tank was up and running all you do is take media from your tank and add it to the new tank you were starting and off you went. As long as you add fish slowly over time. All would work.

Ok now to the original question. Will bacteria grow on media just floating in the tank. Yes it will. But if your fish load doesn’t change will it still grow? Bacteria grows to the fish load so if no new fish why than will it grow?
 

Sorg67

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Seems to me that the bacteria should establish on all surfaces but more strongly on surfaces with water flow. And that it would even out over the entire tank proportional to water flow at a level consistent with bio load. So if you had two filters, it seems like each filter would have a lower bacteria concentration than if you had just one filter, all else being equal.
 

oldsalt777

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Sorg67 said:
Seems to me that the bacteria should establish on all surfaces but more strongly on surfaces with water flow. And that it would even out over the entire tank proportional to water flow at a level consistent with bio load. So if you had two filters, it seems like each filter would have a lower bacteria concentration than if you had just one filter, all else being equal.
Hi Sorg...

Excellent observation! Here's just one example of the benefits of large, weekly water changes. Bacteria is really no different than the fish and plants. It requires oxygen and a nutrient source to thrive. By simply changing most of the water weekly, you maintain a steady source of oxygen and minerals in the water. A perfect environment for everything that lives in the tank. Mechanical filtration does very little to keep the water clean. It mixes oxygen into the water and takes in polluted water and returns the water a bit less polluted, that's all really. The tank keeper is the true filtering system. You remove old, toxic water and replace that with pure, treated water. So, two filters aren't really twice as good as one. The bacteria is distributed throughout the tank, on all the surfaces. So, as long as you change most of the water every week. You maintain a balanced system, just like in nature.

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Momgoose56

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oldsalt777 said:
Hi Sorg...

Excellent observation! Here's just one example of the benefits of large, weekly water changes. Bacteria is really no different than the fish and plants. It requires oxygen and a nutrient source to thrive. By simply changing most of the water weekly, you maintain a steady source of oxygen and minerals in the water. A perfect environment for everything that lives in the tank. Mechanical filtration does very little to keep the water clean. It mixes oxygen into the water and takes in polluted water and returns the water a bit less polluted, that's all really. The tank keeper is the true filtering system. You remove old, toxic water and replace that with pure, treated water. So, two filters aren't really twice as good as one. The bacteria is distributed throughout the tank, on all the surfaces. So, as long as you change most of the water every week. You maintain a balanced system, just like in nature.

Old
Two filters are better than one if you have a huge bioload and a limited space for biomedia in only one filter. You can overwhelm a filter's ability to handle biological waste byproducts. This can happen in tanks when surface area with water flowing over it is too small or there isn't enough waterflow over the available surface area. That's why flow rates are important when selecting a filter for a tank and why additional biological media in a filter helps when overstocking a tank.
 

oldsalt777

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Hello...

Actually, if you follow an aggressive water change routine, you can go with one filter and gradually increase the amount of water you change. Since you're taking the time to get out the gear to change the tank water, just take a few more minutes and instead of removing and replacing the recommended one-third, remove half or even 60 percent. This way, the single filter is simply filtering water that's already clean. A tall, narrow tank, can work well provided you increase your weekly water change, this will ensure the water is always high in oxygen and free of nitrogen from dissolved fish waste material.

Here's a tip for those who for lack of space must keep a taller tank. Research the water temperature requirements of your fish. Most times, fish can easily tolerate a bit lower temperature. If this is the case, gradually adjust the temperature to the lower end of their suggested temperature. As we know, cooler tank water holds oxygen longer than warmer water. Cool water slows the fishes' metabolism, so they poop less. This keeps the tank water cleaner.

Old
 
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