Moving House

to keep you filter cycled keep all of the media wet.
if you change the substrate, you may go through a mini cycle depending on yuor stocking

submerged works best, because that is normally what the media is like when it is in the filter

You could try keeping the some of the old substrate wet as well and put it in a mesh bag in the new tank temporarily to help avoid cycling problems

I'd use some of the current tank water to keep the filter media wet, and to transport the fish, but I really wouldn't bother with trying to keep most of the tank water. The bacteria colonies are in the filter media, and to a lesser extent, the gravel. Not the water.

The suggestion of preserving (wet) some substrate is very good advice.

This is all assuming that this move happens quickly... From the time you tear the tank down till the time you have it set up again, how long do you anticipate?


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