Changing Tank Advice please

[DebzN]

Since learning more about fish keeping I got a 200 litre with sand, wood, rocks and live plants. I now look at my old 120 litre that I've had for years with gravel and silk plants and in my eyes it looks so tacky in comparison. So, I'm going to upgrade that one to another 200 litre set up with the same as my most recent tank. I'm a bit concerned about the fish as they would have to go straight into the new tank once set up. I'd be grateful for any advice on best way to do this. I've considered running the old filter alongside and maybe keeping some of the tank water but not too sure

 

[gwand]

I cycled a 29 gallon tank in two weeks using two filters I took out of a cycled tank, and using a bottle of Tetra Safe Start.

 

[BigDog]

Keep as much of the original water you can.

This will help cycle the aquarium faster

 

[Essjay]

Water won't help cycle the aquarium as the bacteria we need to grow live in the biofilm which is firmly attached to surfaces. They do not live floating in the water.
The only time using old water is useful is if water changes have not been done regularly and the water parameters in the tank are significantly different from tap water.

Do you intend keeping the original tank running, or moving everything to the new tank and closing the old one?

If you don't intend keeping the old one running, you just need to move everything over to the new tank. The current filter should hold the majority of the bacteria in the tank, though there will be some on other surfaces. If you intend using a different filter in the new tank, move all the media from the old filter into the new and fill any spaces with media which is supposed to be in the new one. Sponges can be cut up to make them fit; ceramic media can be put in a mesh bag.

But if you intend keeping the old tank running, the easiest thing to do is take up to a third of of the media from the old filter, filling the spaces with media from the new filter, and do a fishless cycle. Because the old media holds a lot of bacteria, just not enough, the cycle will proceed very quickly.

 

[DebzN]

Water won't help cycle the aquarium as the bacteria we need to grow live in the biofilm which is firmly attached to surfaces. They do not live floating in the water.
The only time using old water is useful is if water changes have not been done regularly and the water parameters in the tank are significantly different from tap water.

Do you intend keeping the original tank running, or moving everything to the new tank and closing the old one?

If you don't intend keeping the old one running, you just need to move everything over to the new tank. The current filter should hold the majority of the bacteria in the tank, though there will be some on other surfaces. If you intend using a different filter in the new tank, move all the media from the old filter into the new and fill any spaces with media which is supposed to be in the new one. Sponges can be cut up to make them fit; ceramic media can be put in a mesh bag.

But if you intend keeping the old tank running, the easiest thing to do is take up to a third of of the media from the old filter, filling the spaces with media from the new filter, and do a fishless cycle. Because the old media holds a lot of bacteria, just not enough, the cycle will proceed very quickly.

Thank you. I've got to close the old tank down so I'll use your suggestion on the media for the filter. I understand your point on the water. I do weekly changes so keeping the water won't be much use to me. Thanks again for the help.