YOU SAID:

my fish are rivals and will chase eachother even if it kills them

INTO JAPANESE

私の魚はライバルであり、殺してもお互いを追いかけるだろう

BACK INTO ENGLISH

My fish is a rival and will kick each other after killing

INTO JAPANESE

私の魚はライバルであり、殺した後にお互いを蹴ります

BACK INTO ENGLISH

My fish is a rival and kicks each other after killing each other

INTO JAPANESE

私の魚はライバルであり、お互いを殺した後お互いを蹴ります

BACK INTO ENGLISH

My fish is a rival and kicks each other after killing each other