New set up

[Gibson91]

How long should you leave your tank to run for before adding fish ?

 

[Byron]

A new tank needs to be "cycled." There are some articles in the cycling section that explain this, the reason and the procedures. The cycling should take somewhere in the 2 to 8 week timeframe.

If you have live plants in the tank, and they show signs of growing, and if they are fast growing species (floating plants are ideal for this), you can ignore the "cycling" and add the first fish once you know the plants are OK. Go slow. Post details of the tank, plants, and intended fish and members can advise how to proceed.

 

[Retired Viking]

Some of the best plants to do a planted/silent cycle are hornwort, anacharis, water sprite frogbit and moneywort. You can let them float or plant them in the gravel. They draw what they need from the water and love to absorb ammonia. Very easy to care for.

 

[lazarusthefishboy10]

To be safe, i think you should let it run for a month or more before adding fish. I know it sounds like a long time, but it will be worth it! You wouldn't want to have dead fish in your tank after buying some!
Stay safe!

 

[Retired Viking]

I waited a little over 2 weeks and then I added my fish in shoals of 5 tetras back then and test the water as you go to make sure your tank can handle the fish waste. Now I add at least 6 at a time, Larger fish produce more waste so you may want to add fewer. Over several weeks I added 3 shoals of tetra and never had a reading above 0 ammonia. I also added plants as I went. I am working on my 3rd tank and plan to also do a planted /silent cycle.

 

[Essjay]

If you don't want live plants, here is the link for cycling the tank https://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/ The link explains why cycling is necessary in a tank with no live plants, and how to carry out the cycle.

Using Tetra Safe Start will help to speed up the cycle.

 

[Metalhead88]

It will take about a month or more, but simply letting it run will not do anything.

You need a source of ammonia to get the cycle going.