Urgent: Please HELP, sick yellow lyretail mollies

Question
Hi,
I have 2 male yellow lyretail mollies, 7 neons, 3 scissortail rasboras, 1 otocinclus catfish in my 20G tank (tank is 3 months old). One of the mollies suddenly became lethargic 2 days ago. He now rests at the bottom most of the times. I observed that he is having difficulty pulling his body up. He is eating less. His tail drooped. There are no white spots or bleeding gills. Now the second molly also is becoming sluggish and hangs around the heater. The other fishes are doing great. The water parameters and temp (78deg) are in the safe zone. I also put salt 1spoon for 5G of water. I used to do water changes at least once a week, but since the mollies are getting sick I am changing 40% water every 2 days. I do gravel cleaning once in 3 weeks. i also put water conditioner as per the instructions. The fish food includes flakes, tubiflex and algae wafers. I don't understand what is going wrong with the mollies as they were very active 3 days ago. PLEASE HELP... I don't want the mollies to die.

Answer
Hi Pallavi,
 I can't see anything wrong from here. It is great that you are doing the water changes and the temp is good.  You do not need the salt -- it doesn't actually help anything and in fact it will keep building up as you do more and more water changes so I would stop adding any salt.

 I assume that uneaten food is not accumulating and that you have a proper filter in the tank?

-- Ron
  rcoleman@cichlidresearch.com
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