How to safely upgrade tanks

[iheartcories]

Hello!
I have a 10 gallon tank with 4 cories and a pleco. I just got the accessories to upgrade to a 20 gallon but want to make sure and do it as safely as possible--though I'm also secretly hoping to not have to have two tanks running at the same time for very long. I've been reading a lot but haven't found a post that matches my circumstances exactly.

I am planning on transferring everything -- sand, the large cave, all fish, and will run both filters for as long as I need to. Will that be enough bacteria in the new tank to transfer everything at once, or do I need to leave my old tank as is while I cycle the new tank from scratch (with as much seeding material as I can steal from my 10 gallon)?

I was also thinking of hanging the filter pad from my new filter over the edge of my 10 gallon for a bit to let it build up some bacteria -- is that useful or not really?

Basically, what's the best way to go about this?

Thank you!

 

[librarygirl]

Hi! You can run both filters on the new tank. YOur current filter has enough bacteria for your current fish so moving it over to the new tank and then running the new filter and moving everything over is fine, you shouldn't see any toxin spikes as long as you use the old media. You can also move the media over from the 10 gal filter into the new filter and then fill the rest up with new media, either way would work. What kind of Pleco is it?

 

[Galligak]

I haven't done this exactly like you but I've done somewhat what your doing. I would just transfer everything over to the larger tank and watch the parameters. Keep them in check. There should be a mini-cycle but nothing much.

 

[jcolon]

Your initial plan is fine ... that's what I'd do. If by chance you were looking to do a new substrate instead of the sand in your 10gal, then now's the time.

The bulk of your bacteria is in your 10gal filter media, so I'd say stuff that filter media into your new filter so it seeds. However, if you can run both filters ... I'd say go for it. Your new filter will eventually get bacteria.

The amount of BB is dictated by the bio-load of your fish, so just upgrading to a larger size will not mean you'll get much more BB, but you'll eventually establish a colony in the new filter media.

 

[Phranque]

Just move everything over (including the water). It's not the tank itself that you cycle, it the filter media, which you already have done. When you move everything over and add the additional water to fill the volume, you are diluting your previous tank water by 50%, which is no different than doing a 50% PWC.

 

[senemedar]

I've just done exactly the same think about two weeks ago - upgraded my tank from 100l to 165l and just moved filter and water from the old tank into the new. I had a new gravel and new decorations and didn't use the one from the old tank.
Just make sure you keep an eye on water parameters. My Nitrites rose up to 0.1ppm after a few days but I did three 20% water changes and everything went back to normal.

 

[iheartcories]

Thank you for all of your help!

I'll stick to my original plan of transferring everything, running both filters for a while in the new tank, and hanging the filter pad for my new filter over the side of my old tank for a bit to help jump start the process.

The pleco is a Bristlenose so it won't get too big for my tank.