PlanetCatfish.com

Hello,
I have an established tank and want to move the occupants to a larger unestablished tank. The filter media for the larger tanks' filter has been sitting in the established tank for 2 weeks. My question is will I have to completely cycle the new tank? If so I'm planning on doing this with ammonia (fishless).
I was wondering if I could just move everything to the new tank, including the filters currently running in the small tank, and add a the new, larger flow rate filter with already seeded media? I thought this may be possible as the bioload will not change from tank to tank, just the volume of water.
This upgrade coincides with me moving to a location with harder water than my current location. Any tips on acclimatising my fish to their new water chemistry also apprecated.
By the way, it's a 35L coldwater community I'm hoping to upgrade to 90L.
Thanks for any help to these questions.
Pete

I was wondering if I could just move everything to the new tank, including the filters currently running in the small tank, and add a the new, larger flow rate filter with already seeded media? I thought this may be possible as the bioload will not change from tank to tank, just the volume of water.

IMO this is the best method for your situation. Extras: not much food after the move for a couple of weeks, and test the water quite regular to make sure you don't get an ammonia/nitrite spike.

This upgrade coincides with me moving to a location with harder water than my current location. Any tips on acclimatising my fish to their new water chemistry also apprecated.

How much harder? goldfish have quite high toleration when moving into harder water. Just float the bag and add water slowly every 5 minutes for about an hour or less.

Thanks magnum,
I was worried about any spiking harming the fish with this method but it does seem the most sensible way to do it.
Pete

If you are transferring the entire contets of the original tank (water, subtrate and all) then I'd say your plan is almost foolproof. Good luck.