Keep Tropheus only with very similar fish, if you must keep them with any other fish.
Similar means diet and digestion. Eretmodus is a good example. Keeping Tropheus with Frontosa can be done, but their diet is very different. I wonder if keeping Tropheus with dissimilar types of fish contributes to the problem with Bloat.
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But the also say
Many people consider duboisi to be aggressive as well. I believe them to be less so than most think. They tend to do very little infighting. Usually when you get a good group the order seems to get set and varies little after that. They all seem to know their place and don’t move out of it. I do find duboisi to be a bit more fragile than the other groups. It seems if you upset their order, the whole group suffers. duboisi don’t seem to pay much attention to their tank mates, kind of like they are oblivious to it all.
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It will be a chance you take you will be gutted if you lose them