Basically, you just described a Fahaka puffer. They get big, up to 18", so a 180 would be perfect, that's what I have mine in. Tons of personality, probably the most interactive fish available. Not too expensive, young ones go for SHORT money and they grow fast. Not picky as far as lighting goes. Carnivorous and very entertaining to feed, eats shrimp, clams, mussel, snails and will actively and relentlessly hunt and eat crayfish. They are a very intelligent and dedicated hunter, a fish that will actually get bored without stimulas. Fairly uncommon, there are very few people that are willing and able to give a large enough tank to a solitary fish that is so brutal to other fish that biologists have wondered how they actually breed in the wild without killing each other.
Can you tell I'm a big fan of Fahaka's? To summarize, if you like big, different and aggro and can give them the room, they are an awesome pet, not just another fish in a tank.
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