it really depends on the dimensions of the 125 but i'd say 7-8 if you leave off the weeksii and teugelsi since they both get past 20"+ (however weeksii take forever to grow)
I know to go for more footprint then for taller tanks for bichirs, not a complete newbie lol. got a senegal and grew it out to full size then sold it and got an ornate. been keeping em for a while now, but I am just getting started with these less common specie.
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