moving fish to new tank

[duffsparky]

Hi all,
Question from a newbie.
My son wants me to move his Malawi cichlids from a 2 foot 50 litre tank to a new 4 foot 220 litre tank.
He has one external bio-filter already setup and running for the 2 footer and various internal filters, one of which is for the 4 footer, that are not set up.
To speed up the transfer process would it be acceptable to:-

Remove the fish from the 2 foot tank .
Install new clean gravel and rocks in the 4 foot tank.
Poor the remaining cycled water from the 2 foot tank into the 4 foot tank.
Top up 4 foot tank with clean filtered temp stabilised water to a level of about 50% of that obtained from the 2 foot tank.
Install the existing bio-filter, new internal filter and heater.
Treat the water with suitable conditioner/stress reliever.
Introduce the fish into the new setup.
Slowly fill the tank over several days with new water to the required depth.
I estimate the initial depth of water to be about 5 inches dependant on the rock displacement.

Kind regards and seasons greetings.

 

[Rbishop]

The existing water will not be that much of a benefit. Little of the good bacteria are in the water column. Most of them will be in your filter media, substrate, rocks and other decorations. The more of those you can put in the new tank, the better.

Even if you plan on different decor eventually, I'd bring the old stuff over. You could fill mesh bags of the old substrate and hang in the outlet flow of the filters, then remove after a while. This way you would not be looking at a substrate swap out later.