aahh the dreaded bloat
bloat is actually associated with stress eg through aggression from other tank mates and or a combination of other things eg food,water conditions etc ,
early indications are fish not eating,white stringy poo ,gasping and hiding in a corner
usually when one fish gets bloat it will affect others in the tank like a chain reaction
so the best thing to do is treat with medication like metro or fluran2 as soon as possible either isolate the said fish into a hospital tank and treat it or dose the whole tank
there are plenty of other forums that have info on this subject
here is some info from The chiclid room companion
QUOTE
Tropheus fear factor by pam chin
Tropheus bring with them two death cards: aggression and bloat. These are the two main reasons for Tropheus deaths in our tanks, both of which are totally controllable. Aggression among these fish can be unbelievable, they have a mouth full of teeth, that are the rasping type and they can de-scale another fish in moments. If you ever see individuals up in the corners of your tank, you better get them out, because they usually don't last long after that. Higher temperatures and poor water conditions can contribute to aggression, just another reason to keep your water changes frequent and massive. If you keep them in large enough tank and a large group, you don't need dither fish, which can sometimes cause more problems. Raising up a young group rather than buying adults is another key to less aggression, when they grow up together they learn to tolerate each other better.
The problem with bloat is that there really isn't a black and white definition of it. When a hobbyist starts losing fish and they don't know what the cause is, they usually say it was bloat. What we do know is that stress appears to be the common denominator. The stress can be caused from poor water conditions, wrong diet, aggressive tank mates, undersized tank, wrong pH, wrong temperature, etc., and when you have a couple of these problems it seems to be a recipe for trouble. Tropheus are worry warts, and any change in their normal routine can trigger stress, like changes in their diet, deteriorating water conditions, moving a long established group to a new tank, or the introduction of other fish whether they are the same species or not.
So, is it a parasite, a bacteria or a blockage?? Actually it might be one or all. What seems to happen is when the fish is under some type of stress, it causes a break down in the immunity system and this can cause all sorts of problems. For example:
1.Parasites/pathogens/flagellates already in the fishes system can bloom, and multiply extremely fast, and since the fish is stressed, it can't fight this off, like they normally would.
2.Sometimes it starts with the slime coat breaking down, which could be caused by a bacterial infection.
3.Over feeding is a big factor along with feeding the wrong foods, which can cause digestive problems and/or blockages in the intestinal track.
4.Other times fish can get what I call reverse bloat, where they actually look like their stomachs are sucked in, and they appear to be starving to death.
Recognizing the early signs of bloat is a big factor in being able to diagnose it. I have only been able to cure it at the earliest stages with Clout. Why Clout works is a debate, as it is a parasitic medicine, but this is the only medication that I have found that works for me. If your first round with Clout doesn't seem to work, there are many who have been known to double the dosage and treat again. At this point what do you have to lose?
Observing your fish, so that you can get a jump on it is critical. Not eating seems to be the first symptom to bloat, but so are stringy white feces, along with vent inflammation, fins clamped tight to the body, and not swimming. Usually once the fish has actually bloated, with the scales sticking out, not just a swollen belly, it is usually too late, their dead. I have killed quite a few Tropheus before I was able to figure this out, now I can see it a mile away.