I was wondering how long some fish keepers leave a new tank to mature before entering your first fish.
Many will not touch it for months with no fish some a week and some would enter 1 straight away.

So here is the question.

4 ft tank ........ say 75 gallons...brand new filters tank etc etc
A Full sized Platy to enter.

How long before you would enter this fish?

Please read "rdd1952" 's pinned post on 'fishless cycle'
All the info is there and if you follow it correctly it works and is even fun

Yes thanks but it was more of an opinion question than a question if you see what i mean

Because i have three tanks i found that when i purchased my third tank i did water changes from the first two but syphoning the water into the new tank. My third tank was 100 gallons and i would say 30 gallons of it was syphoned from the other two plus a thin layer of Gravel from both and a few rocks riddled with algae.
For the first timer i understand if its the first tank as they do not have that option but because of my method on my third i could put 4 or 5 fish in on its first week...What a difference.
The nitrite was very low to start although not perfect but in a 100 gallon tank and about 20 inches of fish it worked well.

I wondered if others with multiple tanks have done the same with quicker results like me.

I guess my question or opinion should have been more specific....It was early

Regards

Ahem, as a rule i never enter fish.

i suppose adding water from a mature tank would help, as would running the new filter in a old tank for a while, then adding it to the new tank, then i'd wait a week and see what the stats are like

This post has been edited by lilfishie: May 19 2007, 01:39 PM

If you have multiple tanks that are already mature you have multiple filters with mature media. Take some of that mature media, and add it to the new filter.

You have to guesstimate the bio load your filters are supporting now, and how much media you will need for the new tank. A mature bacterial colony can double in 24 hours, so you could in theory take up to half from the mature tanks. In actual practice I never take over 25%, it's nice to have a saftey margin. Don't feed the fish in the tank you took the media from for 24 hours after removing some media, less food equals less waste.

When I set up a new tank I take a sponge filter that I have running as a spare in a mature tank, add it to the new tank, add the rest of the appropriate hardware, water, then fish. When it gets slow, tanks get taken down, filters go into a running tank to stay cycled. When it gets busy, I set up tanks, and add sponge filters.