strange clear poop - advice for treatment

[FeGrl]

Hi all,

I have a sick fish and nothing I am doing seems to help, I would appreciate any advice you have.

I have a 2 year old, 200L tank. 0.5in pebble, planted with 8 ~2.5in discus. 0 ammonia, 0 nitrite, 0 nitrate. 32 Celsius, pH 7.4.

She started acting strange ~2 months ago, shying away from the others (but not hiding) and not eating with everyone else - but she is still alive, so she must be eating at some point. She has large, clear poop, and poops a lot - many times a day. I tried ~50% water changes everyday, turned up the temp, and treated with Metro for 1week with no change. Since then I have intermittently tried treating with Metro 2 more times (each time for a week) and still no change. I have attached a pic of the poop (sorry for the grossness). Does this look like Hex to you guys, or something else? Any other advice for treating her?

Many thanks in advance for any help you can give.