Here's what I found looking up vieja melanurus on google
http
/aquavisie.retry.org/Database/Aquariumfish/Vieja_melanurus.html
http
/www.cichlid-forum.com/profiles/species.php?id=102
both of these suggest that 75 gallons is too small. These guys get bigger than oscars, assuming you got the species right. to my knowledge viejas in general get too large for a tank like yours. If you can convince your mom to get you something of a 200 gallon or so, the mish mash of fish (minus the puffers) may work.
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both of these suggest that 75 gallons is too small. These guys get bigger than oscars, assuming you got the species right. to my knowledge viejas in general get too large for a tank like yours. If you can convince your mom to get you something of a 200 gallon or so, the mish mash of fish (minus the puffers) may work.