Elephant VS Elephant battles

[athanaric]

african bush elephants are bigger than the indian ones arent they? would they just crush mine? i still havent tried it yet and i only have one unit of skirmisher cav which isnt doing all that much since carthage brings 3 units of these beast and i only have one

Strictly speaking, they are bigger, however IIRC the regular Indian elephants have similar attack and defence (and HP). As I said, cataphract elephants should beat all other elephant types thanks to armour, discipline and javelins.
Bush Elephants are the easiest to rout (they have the lowest morale value of all recruitable units in EB), so you should try archers with flaming arrows too. If you have too few skirmishers in your field army, you could hire one or two units of mercenary Peltasts or skirmisher cavalry just to be on the safe side. Even regular Akontistai are super effective against elephants (the problem is that they're almost useless once their missiles are spent).