strange fish loss????

Question
"I had my tank set up nicely and had around 20 neons gouramie mollys just
community fish... Well i moved my fish tank with more than a 50% water change
all my fish unfortunatly floated. Then i left my tank still for around a month
or so and now have started again PH is 7.2 amonnia,nitrate,nitrite is superb
alkalinitly and hardness is great but my fish last less than a day. ?
everything says my water is great ?"

Answer
Hi Matt,
Thank you for your letter. Yes, one thing about this hobby is mysterioius deaths. Here are a few things that could have happened.
First, if you used amonia to clean the glass, any amonia left in the tank will immiediately kill fish.
Second, if you used tap water to fill the tank, that could have caused it, depending on what your city's water is like.
Third, if you had no bacteria culture in the tank, then fed too much fish food, that could instantly kill them.
You can get bacteria at the aquarium supply shop in the product "Cycle." For proper feeding instructions, please read and print out my page:
http://steamboats.com/aquarium.html
I encourage you to try again using my system.
Write back if you want to discuss further.
Nori