I just went back to disease symptoms to be sure about this. But one of the definite signs of Malawi Bloat is white feces. It can show up before the fish gets puffy. A fish doesn't need to be from lake Malawi to get Bloat. Any fish can get it, but all Cichlids are very susceptible to this disease. It is also HIGHLY CONTAGIOUS between tank mates
Every cichlid with the white feces needs to be removed fast.
To help eliminate the blockage you need to put Epsom's Salt in the water. Don't worry it isn't really salt, it's a Magnesium laxative/diuretic.
Different sites recommend different amounts, but what has worked for me is, 2 Tablespoons for every 5 gallons. Do 50% PWC every day and replace with fresh Epsom's Salt. As soon as possible begin treating with an antibiotic made to specifically treat Bloat. Not one that says it treats a wide range of parasites, fungal infections and bacterial infection.
Make sure it specifies that it treats Bloat. Fallow the directions on the package and keep up with the PWC and Epsom's Salt.
I wish you luck, Bloat can spread fast and be deadly.
If you can, Google Malawi Bloat signs symptom and treatment. It will give you much more detailed information than I can here.