Tank with high Nitrite and Nitrates

Question
QUESTION: I have an 10 gallon aquarium with 3 platies, 1 catfish, and 1 guppy (had 2 others that died).  I checked the chemicals before I bought the fish, all was ok.  Then had tank with fish about 3 weeks, changing(25%)water 1x a week.  Then my fish started dying. I do have live plants in the tank and have changed the filter.  I called my local fish store and they told me that my chemical check strips must be wrong if I am changing the water.  However, 2 dead fish equate to me that they are correct.  How do I fix this problem.  The fish store owner told me not to add stabilizer, as it is just a waste and to continue changing my water weekly and that should fix it.  I don't want to loose anymore of the fish.   Should I follow his directions or continue on a different course. The chemical sticks have Nitrites and Nitrates as in the danger zone.  All others are in the stable area on the test strips.  Thank you for your time.


ANSWER: Hi Buffi:  What are the ammonia readings???? I would do a 25% water change every other day until the nitrite levels drop... What exactly were the levels?  Also take a sample of water to the local fish store and have them test it for you... if it the same as your test stripes then you will an answer to your problem.  let me know about the ammonia so that I can continue to answer this questions... dave

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QUESTION: The ammonia rating is between 0 and 0.5 ppm.  My local fish store is about 2.5 hours from my home.  The main reason I haven't taken in a sample.

Thanks.

Answer
So probably... you have an active nitrogen cycle in process.  So just continue the water changes but decrease the volume each day by 5% ... so 25% today, tomorrow 20%, etc.  If you have beneficial bacteria then I would be adding that to the tank after each water change.... are the fish behaving any better???  You may also want to invest in a test kit if possible so that you can monitor this at home (if you do not have one already)... the other thing I would recommend to keep on hand is a product called CYCLE which is bottled bacteria that will help keep your tank from going into the nitrogen cycle.... dave