Thats unusual, Orange Roughy is very delicate and savory, more like lobster or a crustacean, I have never had any problems with it. Digests smoothly and quickly for me.
I eat Smoked Salmon from Cost Co on average of twice per day. I eat tons of Canned Tuna and Salmon, fresh grilled Salmon. I smoked a huge fillet once, Ahi Tuna Steaks seved pink, Smoked Whitefish is great from local Deli's, Sardines, Froze Shrimp, Man you can call me a big Fish eater.
I often eat fish 4 times per day, minimally twice per day.