Bring the fishes low enough to card (roughly 1/4 of their health remaining is a good threshhold to pass). If you don't turn on the automatic gunblade trigger, Squall can't critically hit enemies with his basic attacks.
I was farming Fastitocalon-F and carding them for AP when I realizes that my SEED rank was climbing. Using the speed up function on the remaster allows you to kill more enemies in the same time. The timer for this is locked to your system's speed, not the game's speed. Your rank increases based on battles fought and won (maybe also enemies killed/carded? not sure about this aspect, but this would only be relevant if you went to the desert island, sought out cactuars and specifically let them escape to 'win' battles). If you play the remaster, attaining this seed rank isn't too difficult, just time consuming. Still, there is an option you could theoretically use if you play the remaster.
This is MUCH easier on a different save file.
