I agree with RD and Jexnell, its very easy to say I've had a tank with some juvie Texas and a few oscars work for 3 months, or 5 months or so and its all good, (which IMO, is not enough time to know anything) but then the next day or a month after the youtube shoot, all hell breaks loose, because the alpha male Herichthys finally hits a mature or territorial stage, and the other subordinate cichlids are shredded overnight.
And do they, or do you think they will post that? Probably not.
Here you almost always see mistakes of bad combinations like too small tanks, lousy water quality, in the disease section, and often the connection is "not" made by the aquarist, that most problems are not some mystery parasite, and that the tank should be heavily medicated, but that the stress of bad water quality, and bad tank mate combinations lead to compromised immune systems where normally benign bacteria become problematic.