growth rate will vary depending on lighting and co2 levels. swords are heavy root feeders and will def need the root tabs. they can do well in a pot, just make sure its large enough and you replace the tabs every few months or so. and if you're going to pot them in a bare bottom make sure the pot is heavy enough so the o can't slide it around. that said, your oscar will more than likely shred them apart. but you'll never know until you try...every fish and every setup is different.