. This was very strange for this type of fish as they normally accept to any range of PH and oxygen in your tank and cope with quite poor quality water (Although for best growth I would reccomend you keep your water clean!). They can live in a broad range of tempratures although I would say I found around 22-26 degrees C to work the best . IMO they would do well in a tank which had mainly predators not agressors in as I mentioned earlier if you kept with thinks such as Jack Dempsy's, flower horns etc I would expect the MMB to come off the worst. The ideal companions I would say would be larger clownloaches , quite large eel's (5-15" would be good), some of the larger catfish such as tigs would also work well. The price range is very cheap in the country they orginate from as they are used for the food market there but over here (partly due to shipping and UK's price's!) I would expect to pay around £25-30 per fish depending on size.. The fire eel and golden sev's should definatly be ok and as you said etc I presume you mean other fish with the same temprement as the fish you mentioned so it sounds like it should be good! So what size tank are you going to be keeping them in? It would be best if it was atleast 50G. If you do get them be sure to include some pics in this thread please . I do agree they have sort of the same genetic traits as oscars but I have found these to be a lot more peachful and tolerant of other fish. They have the same 'interactions' with humans as oscars do and mine used to always follow me around when I was walking around in the room with there tank in and they were also great fun to hand feed. You have to be careful though as you dont want to feel guilty all the time at their begging faces and end up causing bad water probs from overfeeding! 
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