Hi I’m kolton I’m 14 and currently have 3 tanks, I’m getting 2 75 gallons and need stocking suggestions I have a Bichir around 5 inches who will also need to be homed in one eventually?

Are there any predator fish you recommend?That question is a little like asking, who should I date, a blond or brunette?
Its very open ended, and hard to reply to, because everyone has personal favorites.
Some people like cichlids, some tetras, some catfish, some oddballs such as gobys, like the one below, but it's already 8", so in theory too big for your tank. I keep it in a 180 gal, and starting to consider it will soon be too small
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Because my rule of thumb I try to hold to for myself, is, for a 75 gal tank, nothing that gets larger than 7.5 inches as an adult (10 gallons per inch).
That goes generally for almost any fish.
Although there are species that simply lay around in one spot all day, so they might be exceptions.
Don't forget about pea puffers. Also you are into nano gobies right homer? Or did I remember you wrong?
Are there any predator fish you recommend?