Up-sizing

[Lynne]

We currently have a 150l tank but have ordered a replacement tank of 350l which is due to be delivered within the next week.
The filter we have already bought for the new tank is a Fluval FX4.
I would just like some advice/clarification for starting it off.
Our existing tank was set up and left running for about 4 weeks before adding any fish. Does the new tank have to be treated the same way or, if we transfer the water from the 150l tank and top up with treated tap water as we already do with the monthly water changes in the existing tank, can we add fish straight away?
I know I have been told that the idea is to run the new filter prior to the fish being added but when our Eheim packed up completely about a year ago we had to go out and buy a new one which was circulating the water straight away and we didn´t lose any fish.
It would be nice to be able to transfer the fish to their new home asap (especially as we do not have a very large living room and having 2 tanks in there would be a bit of a squash!) but obviously would not want to cause any unnecessary suffering or lose any.
Any advice would really be appreciated.

 

[King Fisher]

Adding old tank water from your 150 to your 350 will not seed your new tank with beneficial bacteria.

You could take the filter media out of your pump on your 150 and put it in one of the FX4 media tray's. I'd only advise this if your 150 has been set up and running for awhile.....like a year so you don't create a mini cycle in your 150. The filter media will seed your 350 with BB. If there is no fish in your 350 once you seed the tank you need to keep an ammonia source in the tank so the BB doesn't die off. You can use pure ammonia in a bottle or add fish food to your tank. A raw shrimp in a pantyhose or filter bag that's placed in the tank works as well.

Another option is taking a large scoop of substrate from your 150 and putting it in your 350. You can put this in a filter bag or something similar and simply place it in your tank or your FX4 filter tray.

Once your 350 is seeded with BB I'd run it with an ammonia source for at least a couple weeks before adding fish. Don't max out our tank with fish right away. Add fish gradually over the course of a few weeks. If you quarantine your fish after purchase then this should be a fairly natural transition every 3-4 weeks and spaces out your stocking level in the tank which gives the BB it's time to grow to support the bioload.

I like to run two filters on my tanks. It gives me a working filter if one goes out on me and it allows me to move one of them over to a new tank and instantly seed it with BB. Just an idea for the future.

 

[Lynne]

Thanks for the advise.
We shall just have to wait a few weeks before introducing our fish to their new home!

 

[okapizebra]

Will you no longer be using the old tank? If that's the case you can move everything over immediately, so long as you run their old filter on the new tank.

 

[Lynne]

We are replacing our current 150l with a 350l. We´ve got an Eheim classic 2213 external filter at the moment which won´t be man enough for the new bigger tank hence we´ve bought the FX4.
My partner does partial water changes on our current tank every two weeks - one week he will change about a quarter and two weeks later about three quarters so given that so much of the water is changed (and treated) once a month I am presuming that the sticking point with a new set up is the new filter and medium not having the required bacteria. Is that right?

 

[okapizebra]

All you need to do is run both filters for a while on the new tank, or you can also just move all the old filter media into the new filter.

Yes, you are correct. Most of your bacteria will be in your filter. There is also some on your gravel and decorations, but not quite as much. You can move some gravel over too and that will help.

 

[Lynne]

Thank you, that really helps.

 

[okapizebra]

Hi, did you get your new tank up and running and everything moved over?

 

[Lynne]

Our new tank!

We waited a very long time to get delivery to Spain from UK but it finally arrived about 3 weeks ago.
Put the gravel and water in then the water from a partial water change of the old tank. Plants went in and the filter medium from the other filter was washed out in the new tank. Waited about three days and took a test of the water in both tanks and it was virtually the same. Added 6 zebra danios and left them on their own for 2 days and when we were sure they were happy and we had done another water test we gradually added the rest of our fish. They have all been in their new home now for about 5 days and the only casualties have been the rummy noses so fingers crossed there will be no more but they all seem pretty happy as you can see from the photos.

 

[okapizebra]

Looks great!