Upgrading tank, how long to “cycle”?

[Ariel S]

Hello! 

I am upgrading my 20 gal to a 40 breeder. And I’m wondering if it would be an “instant” cycle or does it need time to settle in? I don’t have much space in the room and Ideally I would like to break down one tank and replace with the bigger one same day (with the fish inside the new tank same day). 

Filter- Upgrading from Aquaclear 50 to Aquaclear 70. Upgrading small sized sponge filter to a large, but keeping the small one as well.  

Moving same fish plus adding 12 new psdeudomoguil rainbows. 

I’m using the same substrate, plants, filter media, and sponge filter. I’m adding more new media to the filter as well since it’s bigger and adding in more plants. 

Thank you! 

[Calvin]

Hi, it should be instantly cycled if your transferring everything over. Just make sure to keep the filter media in particular wet so it doesn't start to die off 👍🏻

Enjoy your upgrade! Exciting times 😁

Edited January 29, 2021 by Calvin

[ChefConfit]

If it were me I'd switch the current tank over to the new filters a week or so before switching tanks so that they are fully seeded, but you should be fine just transferring over the sponge filter and  bio media from the aquaclear. 

If you haven't purchased the new filters yet if recommend saving money by sticking with the ac50 and getting a medium sponge filter instead of the large. The medium is a much more convenient size to maintain. Even @Cory has said he uses the medium over the large for that reason.

Honestly though just the ac50 and small sponge should be more filtration than you need in a planted 40. If what you're looking for is more flow then a wavemaker would be a more effective and possibly cheaper option. 

[Andy's Fish Den]

I have done similar stuff in past, and still do once in a while in my fish room. What I do is, drain water into buckets or whatever you have to hold. Out of the 29 gllon, you should have somewhere around 20 gallons. Put fish, plants, livestock in water. Transfer substrate, rocks whatever into tank. Be sure to keep filter media wet while doing. Once you have that stuff in tank, add in the water and fish, then add in fresh water to top up tank. Put both old and new filters on tank and get them running. It is just like doing a decent size water change on the tank. I wouldn't add more fish at the time you do the switchover, I would wait until the new tank is settled before adding more fish.

[TheDukeAnumber1]

Keep the media wet and also keep it oxygenated. If it sits too long with out oxygen transfer if could die off even when wet. Maybe run a bubbler or just don't let it sit stagnant for too long. (I don't know exactly "how long too long is" maybe a few hours, all depends on the small details)

[MattyIce]

If you Cut back on feeding your fish leading up to the move and fast them for a few days after moving them, you can better control toxins building up in the new tank, if you do need to move the fish same day and there isn’t enough bacteria that survives the move.

 

Personally, I like to add some plants from the establish tank, a handful of gravel, and some hard scape, fertilize, and let the new tank go for a week.  Move the fish/filter/hard scape, as much water as possible from the old tank, and heavily reduce food for 3-4 days while monitoring the fish and testing if there are issues.

IMO That first worry free fishless week creates a stronger foundation making the move and the days following it less stressful on the fish.

 

[JettsPapa]

You mentioned moving the media from the old filter to the new one.  There's nothing wrong with that, but another option would be to just run both filters in the new tank for a while.

[Doug_E]

I just moved from a 20 to 40. See my post here on the forum. It was not instant, took a week and then needed prime and I also added safe start the first few days after adding the fish. 

[L.W. Wetarm]

Keep in mind that the majority of the beneficial bacteria isn’t in the filter....it’s on the rocks, substrate, plants, and sunken ship decoration. 

[JettsPapa]

1 hour ago, L.W. Wetarm said:

Keep in mind that the majority of the beneficial bacteria isn’t in the filter....it’s on the rocks, substrate, plants, and sunken ship decoration. 

I haven't seen any scientific studies, and it certainly isn't my field, but that's the opposite of most of what I've seen and read.  It's always been my understanding that a large percentage of the bacteria is on the filter media.

[Ariel S]

Thank you everyone for your responses!

I think I'm going to start seeding sponges and bio rings for the new filter in a different tank to help get a jump start. I got the tank and the bigger filters as a christmas gift, so I'm trying to use as much of what I already have, instead of purchasing new stuff.