My First Fish & Q? on Second Fish

i agree.. if you've done a fishless cycle and kept the ammonia at 3ppm daily (or higher) then you should be able to add all of your fish immediately. However, since you've already gone a day or two without the full bioload in the tank, there's a chance that some of the bacteria has started dieing off, so you may want to test the water a couple times after you add more fish.. and if you're going to add more fish, doing so within the next day would make your life a lot easier. If you're not going to do it within the next day, i would recommend that you add fish slowly

i'm a little confused on the 0 nitrates, but keep an eye on it as you add more fish.
 
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