My Columbian Catfish

Question
Hi Ron,
I've had my sharks for about 2 months now. They are about 3' each and housed in a 60g tank. The tank contains 2 small pieces of Malaysian Driftwood with java fern attached. I also have a Castle decoration for Hiding and some other brackish plants that came from my LFS. I'm not sure which plants they are, they kind of look like java fern but are thinner and lighter in color. I've tested the water and everything is coming out normal. I do a 10% water change every week. The filter is fluval and it's meant for anywhere from 45g - 120g i think.
  When I first brought home my sharks they were doing great. They were very active day and night swimming back and forth on the tank and they were always hanging out together. About 2-3 weeks ago they became almost lethargic. They occupy the side of the tank that has castle. One is very dark and he is the one that spends most of the day in it, and the other two hang around just outside of it in the brackish plants. This is also the side with the light that is suitable for fish and plants, and is on the opposite side of the filter. The two that hangout on the outside are very light in color. When I received them they were all the same med-silver. Their eating habits are just as healthy as ever. The Specific Gravity is about 1.008. I'm not sure what's wrong. They should be more active than they are. I''m worried they might be sick. There is also no growths or fungus.

Answer
Hi Alex,
 I think you need to do more water changes.  In general, I recommend that you change 25% of the water in the tank once a week, every week.  I suggest you start doing that and see if the fish perk up.

-- Ron C.
  rcoleman@cichlidresearch.com
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