Seeded cycling

[Latro]

I'm starting a new aquarium. It's 60 gallons and will have 6 discus in it. I have a 36 gallon setup with 3 discus in it already. I'll be buying the 3 new fish and putting them in the 60 gallon tank by themselves before I move my established stock to the new tank.

I have the 60 gallon tank filled with its filter and heater installed, and have started cycling. I moved one of my pieces of filter media (my biowheel, specifically) from my 36 gallon tank to my 60 gallon tank, to speed up the process. About how long should I expect this to take? Keep in mind that it will only be half-stocked for 1-2 weeks while the newcomers get settled.

Also, should I get a divider for the period when the newcomers will be alone?

Thanks!

[Trevor W]

First off in my experience there is no exact time frame that it would take to seed the new tank with enough BB to be considered cycled. The only real way to know exactly when the cycle is complete is by testing the parameters during the process, the same as a fishless cycle. However the amount of ammonia that the BB can process is subject to the bioload in the tank. BB will grow and die off depending on the needs of the tank. So you can see the variables that exist.

Secondly are the new fish coming from the same source as the fish you already have? If not then you are basically skipping the quarantine process because you used the filter material from your existing tank, even with fish from the same source it is still wise to quarantine the new fish from the fish you already have.
I personally have only used seeded sponges when setting up a new tank when I am moving my current fish to a new tank or dividing up my existing fish whether its to split up aggression or set up a breeding tank or just due to them out growing their current tank, ect....

In short there IMO is no way that anyone on here could say that your new filter will take exactly or even roughly X# of days to be seeded, but I am sure there will be lots of people that will disagree with me. This is all just my personal opinions from my experiences. For example I could setup a new tank with a brand new sponge filter and seed it with a inuse sponge filter and I would just transfer the fish at the exact same time because the transfered sponge coupled with regular water changes will be enough to handle the fish I am putting in there, but I couldn't tell you exactly how long it would take for the brand new sponge to become cycled or seeded enough to handle the fish on its own.

Not sure if this answers your question or not. If it were me I would keep the fish and all their filters seperate from one another until the quarantine process is finished and you are confident that there are no issues.
Simply putting them all in the same tank right off the bat and adding a divider is pointless because there is no quarantine. I have only ever used a divider when I am short of tank space and a pair forms and I want the pair to do their thing or minimize the aggression until I can setup another tank.

[Trevor W]

I see now you were asking if you should divide the 60 while the new 3 fish are in there and yes that could be beneficial depending on the size of the fish. If the fish are small than adding a divider while they are alone might be beneficial so that they feel a little more secure and have no troubles finding food.
Thinking some more about this now, if I were you I would take my entire filter from the 36 and transfer that and my existing fish to the 60 and then sterilize the 36 and add a brand new filter and use it as a quarantine for the 3 new fish.

[Latro]

One of my fish is not from Hans, the other two are and the new fish will also be from Hans. I've had them for a bit over 2 years now, and haven't had any health problems. I bought the two from Hans as 4 inch fish, and the three new ones will also be 4 inch fish. So the sorts of issues that juvies have with food should be absent.

Are you sure about the quarantine issue with just sharing a piece of filter media, especially after the tank has been running empty for at least a week?

[Trevor W]

Hi Latro,
I was just using Hans or any other sponsor as an example. I personally only seed tanks with inuse established filter media when moving existing stock between tanks because there is no need for quarantine. I take the filter material and switch it to the new tank and add the fish at the same time as the filter material because the BB will die off if there is nothing feeding it and it does not need to cycle because it is already established.

For example: I personally just recieved a small group of new fish and when I set up the tank for them I did not use any existing filter material or equipment from any of my other tanks to prevent a possible cross contamination rendering the qt pointless. To some this may seem overboard but equipment for freshwater fish is cheap or atleast compared to the fish and other aquatic hobbies like saltwater. When I do my water changes I do not use the same hoses. My qt tank has its own hose and nets and after qt I sterilize these as best I can and they get put away until they are needed again. Like I said this is just me, other people may find this overkill but I enjoy the peace of mind. Yes it may be that the filter material is safe and is not harbouring anything potentially bad, but I choose not to take the risk because I have no way of knowing forsure until fish are introduced.

Being that your filter material has been in a fallow tank for atleast a couple weeks it will not be growing or really seeding anything because the BB grows and dies off due to the bioload, so your tank will likely go through a cycle when your new fish are put in there anyways. Due to the frequent water changes that most people do, small cycles are no big deal really because you are changing a large portion of the water frequently. However this then takes the cycle longer to complete and if you miss a day or days of water changes this can show ill effects on your fish. If your set on just doing it this way then get a bottle of tetra safe start or seachem stability and dose that during the first week or so as well as doing water changes. Some don't believe in the stuff but I know alot of people who do. I have used them in the past and they have worked for me or so it has seemed.
Either way best of luck with the new fish and post some pics when you get them, everyone loves seeing pics :)

[Latro]

I see what you mean. Yes, it does seem difficult to get a bioload sufficient to maintain a group of fish with a fishless cycle. You can add food or (unmodified) household ammonia, but inevitably your fish will generate more than you add. The key is to have them at a level where it will only take a few doublings to get to healthy levels, rather than 10+ doublings.

I see your point about cross-contamination now. It seems much less severe than actually putting the fish in contact, but I agree that the risk is still nonzero.

I've been doing the usual procedure for fishless cycling, so there is some bioload even though it is considerably less than a stocked tank.

I think just stocking the tank with the newcomers, getting them a divider if they have trouble finding food, and doing frequent water changes should be OK. Maybe I'm overconfident, it's just that the only trouble I have had in my ~two years with discus hobby was with buying some fish from a bad supplier, and I'm not doing that this time.

I've seen a lot of skepticism about the bacteria products. I think I'd like to see at least one other positive opinion before using them.

Pics will ensue.

[Trevor W]

I see what you mean. Yes, it does seem difficult to get a bioload sufficient to maintain a group of fish with a fishless cycle. You can add food or (unmodified) household ammonia, but inevitably your fish will generate more than you add. The key is to have them at a level where it will only take a few doublings to get to healthy levels, rather than 10+ doublings.

I think you mis understood me or perhaps I didn't word it correctly. I have used fishless cycles lots throughout the years and have never had a problem with getting a good amount of bacteria. I have only ever used ammonia for I feel that rotting food just isn't as effective.

I see your point about cross-contamination now. It seems much less severe than actually putting the fish in contact, but I agree that the risk is still nonzero.

Yes definatly not as severe as putting the fish together instantly, but I just like to eliminate the possibilities.

I've been doing the usual procedure for fishless cycling, so there is some bioload even though it is considerably less than a stocked tank.

Well if you are adding ammonia and monitoring it than I see no reason why the BB wouldn't be there. I was unaware that you were adding ammonia or food like a fishless cycle.

I think just stocking the tank with the newcomers, getting them a divider if they have trouble finding food, and doing frequent water changes should be OK. Maybe I'm overconfident, it's just that the only trouble I have had in my ~two years with discus hobby was with buying some fish from a bad supplier, and I'm not doing that this time.

I've seen a lot of skepticism about the bacteria products. I think I'd like to see at least one other positive opinion before using them.

I too have seen alot and part of me is skeptical aswell, I thing the main thing is understand what it actually does and what it does not do. Having a realistic expectation when using it is the first step IMO. I think that it works more in that it prevents the built up ammonia/nitrite from becoming toxic similar to what prime does. But I like to think that it atleast aids in establishing a colony of BB. I have no exact proof because I have not done a scientific study using a control tank and a additive tank, but I like to think that in certain situation it may help to a degree as long as the person doesn't expect it to be a magic little bottle full of live bacteria that will instantly colonize your filter material.

Pics will ensue.

All the best with the new fish! How big did you say the new fish will be?

[Latro]

I definitely wouldn't expect my established media to retain their BB without some bioload. They need to eat too! Plus, the available surface area in this filter is considerably larger than in my 36--2 biowheels and 2 cartridges instead of 1 biowheel and 1 cartridge. So there's some room for them to spread. I'd never assume seeded media would remain seeded for more than a few days without some food input.

I'm getting 4 inch fish.

[Trevor W]

Fair enough but I was not sure because you never said anything about adding a "food source" for the bacteria until the quoted statement above. I was not trying to assume you are stupid or anything like that, sorry if I came across as that but like I said you just said that the moved media was running in an empty tank for atleast a couple weeks.

4" fish I personally wouldn't worry about them having troubles finding food in a 60Gal, but thats just me.

[Latro]

You're fine. I naively assumed that "have started cycling" would make it clear that I was adding nitrogen. I can understand how a beginner might have heard the term and thought that just running the tank without anything in it is what "cycling" means, and I did put this in the beginner's section after all!

Thanks for the comment about the size.

[Latro]

As promised, a pic of the whole group together. I'm a little sad that I kept my adults as a group of three for so long, seeing how much more comfortable they all are in a group of six.

http://i.imgur.com/LdBRQSg.jpg