question on cycling a new filter in an established tank

[venzi]

Hi.  I have a nearly 1 year old established tank that uses a UGF.  I've been wanting to cycle a new filter to use as a backup in a quarantine tank and I finally purchased a new pump/sponge filter combo.  Now, if I just leave it running in my established tank, then how long do you think it'll take to get it ready to biofilter 1 or 2 fish?  Or will it like never cycle b/c there's just not enough ammonia in the water of an established tank?  Thanks.

[Galabar]

Does it have some location for media?  You could place a small amount of gravel from the tank into the new filter.

I'm not sure if nitrifying bacteria "floats" around in large quantities.  So, seeding might help.

[_Eric_]

A new sponge filter should be “seeded” after about 2 to 3 weeks.  Fish are constantly emitting ammonia.  It probably wouldn’t have a massive colony but enough to handle a fish or two without a dramatic spike.

[venzi]

Sweet thanks all for your replies.  I guess I'll experiment in a few weeks to see how well it does 🙂

[lefty o]

a few days will get it well seeded with bacteria. longer sure doesnt hurt, but 3-5 days will do the job. does not take long for bacteria to colonize.

[venzi]

On 8/30/2023 at 12:04 PM, lefty o said:

a few days will get it well seeded with bacteria. longer sure doesnt hurt, but 3-5 days will do the job. does not take long for bacteria to colonize.

I'm trying to understand if there's a nuance here b/t "seeding a filter" vs "seeded filter".  So there's the idea of "seeding a filter" with some existing bacteria colonies from an established tank (through gravel, filter media etc).  I'm familiar with this idea of seeding a filter.   But what exactly does it mean for a filter to be seeded?  

My best guess is that the filter has enough variety of bacteria established in it to support the entire nitrogen cycle?  It's kind of hard to believe that what takes typically weeks to accomplish when cycling a new filter from scratch to be done in 3-5 days.  Am I missing something?

[lefty o]

there is no nuance, as far as im concerned. in comparing seeding/seeded filter to establishing a complete new bacteria colony, with the new filter into a seasoned tank, you already have the bacteria, it just needs to colonize the new filter vs starting with no bacteria in a new tank etc. now i dont care if you do it for 3 days, or 3 weeks you cant stick it in a new tank and instantly fully stock the tank. really want to jump start one, as in you need one in a hurry. stick your new sponge filter in your seasoned tank and rub it all over the glass. once you have the bacteria, they multiply rapidly, you just have to give them reasonably decent water, and feed them. if someone is going to wait 3 weeks, may as well just stick a new filter in a new tank, and do the old fashioned "cycle" a tank. in the end, go with your gut, and do what feels right to you.

[Galabar]

I would agree that just dropping a new sponge filter into an established tank is not nearly as good as doing something to help the bacteria in the tank to come in contact with the new filter... 🙂

 

[JChristophersAdventures]

@venzi If you want to be certain, then after the 2-3 weeks, place the sponge filter into the tank where you will be using it, then add some Fritz Turbo Start (according to the directions for a new tank), maybe a little fish food to help all that new bacteria along and between the 2 beneficial bacteria sources you will be good to go... just remember to test often. Thanks.

[gardenman]

What you mean by "1 or 2 fish" matters a bit. If the one or two fish are full grown arowanas, or other large fish, you'll get one answer. If they're cardinal tetras, you get another. Realistically, if you put the new filter in the old tank for even a minute, it'll pick up some good bacteria. The longer the new filter media stays in the established tank the more bacteria it should grow up to its maximum capacity. You don't just want your bacteria in the filter though. You want it all through the tank.

I'd be inclined to run the new filter in the old tank for a day or so, then move it and a handful of the gravel from the old tank to the new tank without rinsing or washing the gravel. That might give you enough bacteria to handle a small bioload immediately.