starting a new tank with old filters

[climber05]

hi guys.
i just got a new 4ft tank. it was only emptied by the previous owner today and the filter is completely cycled. after dechlorinating the water and  puting old filters back in how long should i wait before adding fish???
thanks in advance.

[nemo1981]

i have setup new tanks on neutralized tap water and on cycled filters and added fish straight up with no losses.

but that's me, i can't speak for others.

[IAMRustyBlade]

[quote:f9754835c1] have setup new tanks on neutralized tap water and on cycled filters and added fish straight up with no losses. [/quote:f9754835c1]
I do exactly the same thing except add a double dose of Cycle and I've never had a loss as a result either. I've set up many new tanks this way.

[LordFlashHeart]

Yeah you gotta start making ammonia for the bacteria to eat so leaving it fishless for too long would not be a great idea.

[GTR73]

I started a 4ft with the canister filter, the fish and all the substrate and rocks from an established 3ft tank and had no dramas at all. Only after a few months did I slowly add more fish.
Certainly get some fish in there to keep the established filters cycled, but worthwhile factoring in the amount of substrate, rocks and fish that were kept with those filters. People sometimes underestimate the biological capacity and input into the cycle of the substrate and rocks.
What would be ideal is transport everything from your old tank, if you're upsizing, into the new tank.
If you have completely new gravel and rocks I'd certainly estimate a smaller amount of fish that were previously kept with those filters.

HTH

[Davies da fishman]

hey,

so long as the filter media has been kept submerged and it hasnt been too long since the filter stopped cycling then the bacteria in it should still be alive and ready to start working on fish waste in the new tank. also make sure the ph is around the same as in the old tank and u shouldnt have a prob...

worked for me more times than i can remember

matt