paralyzed guppy

Question
Is there any cure for a paralyzed guppy?  High ph levels may have been the culprit.  I had the same thing happen to another guppy first, but this one has been hanging on in my sick tank for a couple weeks.  He can't move to feed off the top of the water, so I'm hand feeding it (I can't believe I'm doing this!)  He is curled up and floating on the top (still moving his side fins and very much alive).  At the first sign of being sick he was unable to swim normally, then eventually curled up and couldn't move.  Are there any other reasons that could've caused this?  I have a ten gallon tank and the other fish seem to be doing fine now that I've done a 50% water change.  Although with my last water test, the nitrate is 80-160, the hardness is 150, the alkalinity is low at 0-40, and the PH is acidic at 6.2-6.8.  Although the water out of the tap that I use in the aquarium is very alkaline at 8.4.  Also, my live plants have quite a bit of alagae growing on them.  Please help!

Answer
Hi Kelly,
 There is nothing wrong with that pH, but you have a lot of nitrate.  Are you doing regular weekly water changes?  You should be changing 25% of the water once a week, every week, to keep your fish happy and healthy.  

-- Ron C.
  rcoleman@cichlidresearch.com
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