Thanks all for the nice welcome!
Just to give an update on my tank after our trauma last week:
We still have two of the large silver tetras and the golden chinese algae eater left. The fins have stopped eroding, and they are eating and playing well. I keep doing 20% water changes every day because my nitrite levels are in the stress zone. The rest of the tests seems to come out in the normal, neutral or safe range. I'm assuming that I'm in the middle stage of cycling from what I've read on everyone's posts and links.
My daughter loves to help me use the gravel vacuum to clean out the tank, so we make it our project when I get home with her each day. And I feel a bit better considering the amount of money I have invested into the tank that I at least have some inkling of what's going on now thanks to this community.
Much appreciated thanks and blessings to all!