I fert mine with Seachem Excel once a week after a WC. They grow fast enough to be split every 2-3 months. My severums do not bother the anubias or the java ferns. I can't speak for oscars but severums are as close as I can get in destructive behavior.
EDIT - Flourish, not Flourish Excel, sorry
75 gal, 1 gold & 1 green severum, blue acara, mating kribs, bolivian rams.
29 gal planted, 1 festivum, 1 bristlenose, emerald cories.
29 gal planted, 1 rainbow cichlid, 1 pearl gourami, 1 bristlenose, mystery snails, emerald cories.
10 gal boblitis\java fern nursery.
Last edited by aceranch; 12-21-2013 at 05:30 PM.
Reason: correcting my error