i need help

Question
hi i got a freshwater tank a couple of weeks ago changed the water weekly and all my fish are dead now. i have had mollies to betta's i don't understand why on every tuesday they all die. the guy at the pet store sold me a fishtank for new users it's only 2.5 gallons i think there's something wrong with the tank because all the fish have died from being in this tank i don't get how in 3 weeks all my fish have died. please help me if you can thank you.

Answer
Hi Danielle,
  When you say that you "changed the water", do you mean that you changed ALL the water?  You should never change all the water at once.  You should change at most 50% of the water at once, and 25% is a much better amount to aim for.  When you add new water, be sure that it is roughly the same temperature as the water in the tank.  Also, if your water supply has chloramine added (as does the water in many major cities) then you need to treat the water with a chloramine remover, such as Amquel, before you put the water in the tank.  

 It is also essential to only put a very few fish in a tank that size.  For instance, I would only put a single betta in a 2.5 gallon tank.  

-- Ron
  rcoleman@cichlidresearch.com
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