I have read a lot about the aggressiveness of this fish as well as the Blue Freckled Monster. Does anyone have any knowledge of these two species?
Also, has anyone ever kept the 2 species in the same tank successfully?
I would look at this site, the guy here said that they get very large and they are built to kill everything else in the tank... his killed RDs and Jags so I would be careful
big mean cichlid for sure. umbees are the same. they may get pushed around when smaller but the reason is that they are much larger fish and mature later. midas and the like will usually dominate till 7 to 8 inches when it becomes a matter of each fish' personality. some will get meaner and destroy midas' and devil's because they get quite a bit larger. that being said i have seen some HUGE midas and devils at steinhart aquarium that could hold their own with all save the largest most aggressive umbee's. the black nasty can be brutal but i have seen an equal number of mild mannered fish. every fish is an individual. your fish will be different from all of ours. try your hand at either species, and i promise you wont be disappointed!!
Vitaliy,
If you are seriously looking for the Nasty, check out Jeff Rapps.
He sells them for $5.50 @ 1". Once I purchase my 2 new tanks,
I will be purchasing a few.