I currently keep a Frontosa with a South American community tank (Blue JD, Oscars, Shovelnose, GT, Geophagus, Splendida Red, Polypterus, and a couple other oddballs). Water parameters are south american.
My Frontosa thrives, he was the smallest in there 3 months ago when I moved him with the big guys, now he aint the smallest anymore. He grew fast, and bosses the bigger fish around. Nobody but my Blue Jack Dempsey and GT can hold him back. He is a great member of this community, I would say go for it. Just watch for signs of over-aggression with the silver dollars (never had those, not sure if they can hold their ground). A Frontosa can be very brutal with other fish, believe me...mine has killed a few fish in the past.
As far as water parameters are concerned, if water temp is decent (79-80) and water is clean, personally I say most fish will adapt to their environment. Even though the Frontosa in nature has higher pH, he is doing perfect and is looking beutiful in my south american-pH tank. You just have to go gradually, don't rush things.
