You should be okay. Rite now the chemicals may be unbalanced (most likley) as things cycle.
Last april I got exited and listened to the petco people without researching... Bought a new aquarium, and after the "sure start" bottle I added my fish after 24 hours... Nothing died in my tank, but later I learned of the stresses I put the fish through until it all worked out. And as of rite now those fish are VERY happy, alive and well fed... So I hope yours have just as much luck as mine did
Things you'll want are a good filter, (I replaced the cheap tetra one that came with mine with a Marineland penguin 100 with a biowheel, biiig difference). A quality heater that wont let tank temps flex too much, and a healthy light source if you plan to have live plants.
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