I'm about to get my 540 gallon tank set up (72"×72"×24" plus a 150 gallon sump). I'm thinking of stocking it with a group of bichirs, a SAL, a small gar (maybe a short nose), a datnoid, and possibly a BGK. I'm not sure if my tank is big enough to have so many large fish in them, or how well their water parameters would align considering bichirs are African, datnoids are Asian and lungfish are South American.
