New Aquarium Need Help Please

Question
I have an 8 gallon biosphere. I set it up two weeks ago using tap water, washing in hot water one fake plant and added the water conditioner that came with the biophere. I let it run for 2 weeks. Last night I purchased a " Mickey Mouse" platy and it died within 3 hours of placing lying on the gravel on the bottom. I do not want to kill another fish due to my ignorance is there anything I should do before purchasing. I do not have  a heater and the room temperature is typically at 72 degrees. Any advice would be greatly appreciated this is my first attempt at having fish.

Answer
Hi Eileen,
 Hmmm... that is very strange.   I assume that you never used any soap or detergent on the tank, right?  

  The tank is pretty cold.  If the room temperature is 72, then the water temperature will be around 68 or 69 (it is always colder than the air).  That's a little too cold for most tropical fish, which really want something up around 75-80oF.  
Any chance you could get a heater?  

 The problem with the first fish could also be due to where you got it.  I strongly recommend that you purchase fish from a fish pet store as opposed to a place that sells many other things.  

-- Ron
  rcoleman@cichlidresearch.com
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