my beta might be sick.

Question
hey my white beta with blue and white fins that was clear and beutiful had recently turned up with black streaks and spots. The body is ok though that part didn't turn black.i'm really worried about it. he is eating well and swiming very much but it's side turned a bit pink and the sides where the gilles  are are big and bulgy like it has cancer or something.the tank is on my desk in a corner it gets light from a desk lamp and no sunlight.and also it turns sharply at a 90degree angle when it swims and goes up on the surface of the water alot.i have never had a fish before so i don't know alot about it.in the tank there is no rocks ,compagnion or plant in it. also it swims alot and kind of looks mental. i  didn't clean his tank yet i just got it on may 31. but i do feed it everyday one pellet a day like the store keeper said and i take a cup of water from the tank and put in new water again like the store keeper said. i do put in clorine as much as the guy told me to put in but only when i completly wash the tank not when i take a cup and refill.please help me. is my beta sick? sorry this question is long it might cover the bases. please tell me more about this .

Answer
Hi Jeanie,
  The stuff you add in (the chemical) is not chlorine but rather chlorine remover.  Chlorine is deadly to fish.  You need to add the chlorine remover anytime you put new water in the tank that has chlorine in it, which includes most city water supplies.  

  There is no reason to completely wash out a fish tank. Doing so kills off all the good bacteria in there that are what really keep the water and the fish healthy.  Stick to changing 25% of the water at a time.

  It is possible that the black streaks are the result of the untreated water that was going in the tank but it is hard to say.

-- Ron
  rcoleman@cichlidresearch.com
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