Jestr, I can completely understand your attraction to the larger more aggressive fish and if the tank were in your living room I would encourage you down that road…
But it’s in your waiting room…
First question we must ask before making too refined of suggestions… what are the dimensions of the 150 gal?
I suggest you look into Geophagus species…
*They are sand sifters and watching them mouth sand and spit it out is quite relaxing…
*Most species are quite docile and therefore will not scare your patients…
*Many species are medium growers allowing for more fish in the tank…
*Many species can be kept in a breeding colony allowing 2~3 males to spawn with 4~9 females and everyone get along peacefully…
*There are a few species of Dwarf Cichlids that could get along with smaller Geo species to add some variety to the tank… Specifically Rams and Apistos…
*If it is a tall tank a large school or two (or three or four) of Neon Tetras, Danios, Tetras, Hatchet Fish, Pencil Fish, etc, etc, etc would add movement and color to the overall set up…
Orange Head Tapajos are a smaller growing, docile, colony breeding fish which has nice color that would suit all of the above criteria and they are readily available at reasonable prices through many suppliers…
But it’s in your waiting room…
First question we must ask before making too refined of suggestions… what are the dimensions of the 150 gal?
I suggest you look into Geophagus species…
*They are sand sifters and watching them mouth sand and spit it out is quite relaxing…
*Most species are quite docile and therefore will not scare your patients…
*Many species are medium growers allowing for more fish in the tank…
*Many species can be kept in a breeding colony allowing 2~3 males to spawn with 4~9 females and everyone get along peacefully…
*There are a few species of Dwarf Cichlids that could get along with smaller Geo species to add some variety to the tank… Specifically Rams and Apistos…
*If it is a tall tank a large school or two (or three or four) of Neon Tetras, Danios, Tetras, Hatchet Fish, Pencil Fish, etc, etc, etc would add movement and color to the overall set up…
Orange Head Tapajos are a smaller growing, docile, colony breeding fish which has nice color that would suit all of the above criteria and they are readily available at reasonable prices through many suppliers…