Once the tank has completed a fishless cycle(not just when nitrates appear) you can add just about anything you want. You don't have to stick soley with the exceptionally hardy fish though also don't get fish that are very delicate either.
I was only mentioning that hardy fish are usually a lot better for starting then get a nice lot of fish at around 4 months! Tropical fish should not be added in a rush
I was only mentioning that hardy fish are usually a lot better for starting then get a nice lot of fish at around 4 months! Tropical fish should not be added in a rush
I'm saying you can add nearly anything you want because if a fishless cycle has been properly completed then there will be no spike of ammonia or nitrites.
As long as the other parameters of the water are proper (ph, kh, gh, o2, co2 and trace metals) then there is no restrictions really. Now would I choose a shoal of cardinals 1 week after a fishless cycle....probably not.
I was only mentioning that hardy fish are usually a lot better for starting then get a nice lot of fish at around 4 months! Tropical fish should not be added in a rush
This is not true, and you should not hand out bad advice.
After completing a fishless cycle you can fully stock your tank immediately and it needn't be with the toughest fish you can find. This is the joy of a fishless cycle. In fact if you add just a few fish they will not produce enough waste to feed the bacteria. This means that when you add the next batch of fish you will see an ammonia spike and a mini-cycle. This is more dangerous than adding all the fish at once, especially since the second load of fish are likely to be more delicate varieties (otos etc) due to the success of the first bunch.
If you have completed a fishless cycle it is best to add all (or most) of your stock at once. Just plan which fish carefully.
