Sick Dwarf Gourami - Please Help Quick -?

I have a male gourami with a swollen belly. He hasn't eaten in 3 1/2 days (since Sunday). Last night I isolated him in a floating breeder tank, in my large community tank. I was absolutely certain based on what I have read that he was constipated and I didn't want him to eat just in case. He was hanging out on the bottom of the tank rather than his hidin in the floating anacarus at the top of the tank. In the 6 weeks I have had him he has NEVER stayed at the bottom so I knew something was wrong. For 4 feedings in a row (twice a day) he didn't eat. Then I noticed his belly got fat. I peeled a cooked pea and put a very tiny amount in the tank for him last night but he didn't eat it so I took it out this morning. Tonight I noticed his belly is less bulgy than last night, however my powder blue dwarf who is staying right next to him on the outside of his floating tank, I noticed their eyes are very different. My powder blue's are normal and my sick gourami has kind of bulgy eyes. I have looked at the pop-eye pics but none of his symptoms seem to match exactly. I don't know if it is a new symptom or if I am just now noticing them because the powder was right next to him side by side. CAN ANYONE TELL ME if all of this matches one illness or do I have overlapping symptoms. By the way part of the convincing part of the constipation was he was kind of swimming sideways almost flat as if it was a symptom of swim bladder problems from overeating. Here all of the symptoms listed: Labored Breathing, Bulgy Stomach, Bulgy Eyes, Not Eating, Not Pooping, Swimming or Laying Sideways when Fatigued. ABSOLUTELY HAS NO PINE CONE SCALES. It is not dropsy (I hope) unless the pine cone scales haven't presented yet. By the way on a completely separate side note I have not changed the quantity of food (minuscule scooper in jar), amount of water changes (25% tonight - Wednesday and 20% on Sunday). On tonight's water change, I HAVE NEVER EVER seen the water so dirty. There was so much poop on the bottom of the gravel. The 1 thing I did different was put some Stress Zyme in the tank for my very first time. My LFS owner suggested that on Sundays water change. Could this have caused the extra poop build-up? I have never used it before. I have had my aquarium set-up with 90% of the same fish for 8 months now- so for all of a sudden extra poopy dirty water just doesn't make sense to me. Any ideas?