Dwarf Gourami

Question
Hi, I have a question regarding my Dwarf Gourami.

I have recently done a 50% water change in my fish tank and cleaned all the ornaments in the tank and changed the two filter cartridges in my filter, leaving the foam for another time (as I know changing both at the same time can poison the fish).

Since doing the water change the Gourami has become lethargic and seems to stay in one place not moving at times 'lying down'. It's breathing is faster then normal. I have checked the pH levels in the tank, they are 4.6 and the nitrite levels are below 0.3mg/l. The rest of the fish are lively and I can not see any signs of disease or infection in my tank.

I know this could just be old age for the Gourami, but I was wondering if you could recommend anything else I should be looking for?

The other fish in my tank are 3 Tetras, a Kissing Gourami, a male guppy, a Tiger Barb and 3 Cat Fish. there are no live plants in my tank either. I thought I would provide this information in case it helps you.

Thank you for your time
Caroline

Answer
Hi Caroline,
 It could be old age, but it also could be the tiger barb attacking the gourami.  It is doubtful if it was caused by the water change. That said, I prefer to stick to changing only 25% of the water at a time to avoid creating too much of a disruption.  

-- Ron C.
  rcoleman@cichlidresearch.com
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