I'm sure either could be done. 35 Gallon should have enough room for 9 Platy, 5 Swordtail easily, but of course you'll have to keep up on water maintanance after they reach fullgrown sized of 3" or so (and the swords at 3-4").
oh and sorry if the bold makes the question look forceful...i jsust want it to stand out...im tryin to do that math or logic to fit 12 but lol i kno that might be too much
