dwarf gouramis

Question
My dwarf gouramis- I have four and one is twirling in circles and one other one looks a little different-sort of brownish in the face and top fin.  The one that was twirling was on the bottom for a while and I thought it would die but it is still alive in a bush somewhere now.  Is there some medicine I should put in the water.  My tank has been set up for a few weeks with live plants, rocks and logs.  The water smells a little musty. I top it off every other day.  It has a heater and a filter below.  It is a big tank maybe 70 gals i think.  Thank you in advance.

Answer
Hi Marcy,
 The water should not smell musty.  In addition to topping off the tank,it is essential to actually take out old water and replace it with new water.  In fact, you should be changing 25% of the water once a week, every week to keep your fish happy and healthy.  That is the most important thing you can do for a fish tank and is much better than trying to add chemicals or medicines.

-- Ron C.
  rcoleman@cichlidresearch.com
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