New aquarium setup mistake

Question
I made the mistake of setting my aquarium up and stocking it too soon.  The aquarium is a 30 gallon tank with an external filter, heater, and I've provided a large air stone with pump.  I added this product by TETRA that states you can add fish as soon as product is added. It's a new product. It states on back that it contains bacteria essential to fish.  I've read many comments about the product not working, now I'm worried about the fish I've purchased.  I have one molly, 2 platys, 6 danios, and three other fish that are livebearing fish. I'm not sure what these fish are called.  My ph is 7.0 and my temp is 75 degrees.  I stocked the aquarium 24 hours after setting it up.  I'm worried now about the cycling process and if my fish will live. What can I do to keep them alive?  Today is day 3 and the fish seem fine.

Answer
Hi Joseph;

If the fish are small, they might make it okay. Watch the levels of ammonia and nitrite (not nitrAte, it's different). If the ammonia or nitrite get into the "danger zone", make a partial water change of 25% to get the fish through it. Monitor it daily when it seems like it could be getting high and make a water change if it is. Just don't vacuum the gravel yet. Let the bacteria colonies get established there first. Feed the fish very lightly and see how it goes. Just don't add any more fish until the tank is totally through the break-in. You could add some live plants though. Two hardy ones are Java Moss and Java Fern. They will come already equipped with their own colonies of beneficial bacteria clinging to them that will "seed" your system and hopefully help things out a bit. Here is a link to my own article about the break-in to help you through;

http://www.xanga.com/Expert_Fish_Help

Frequent partial water changing (25% weekly) is the single most important and effective thing you can do to help keep your fish healthy. I'm not convinced that any additive is going to make any difference one way or the other. In my experience, they are a useless waste of money. Besides, fresh clean water is cheaper and much more reliable than any product money can buy anyway. Just use a plain old basic water conditioner in the new water, nothing else. Keep it simple. ;-)

Good luck!

At Your Service;
Chris Robbins