Nasty fish for a 10 gallon tank

convicts are too big for a 10gal. I would say a betta, dwarf gourami, the shell dwellers popped into my mind as well, or maybe a single apisto?
 
I know this is a little off topic, but if your into saltwater you could get a real nasty creature for a 10 gallon, like a mantis shrimp, those guys are really mean....

Mantis_Shrimp_.jpg
 
So who is this fish gonna be mean/bad and nasty toward??
 
mantis shrimp are very cool animals. but this is a saltwater tank, so im sorta leaning towards that variety.

mean fish towards no one. just one dominant fish for the tank, who has got a reputation. lol rosita, dont look into it too much. i just want a fish that wont take no crap and hide. plus, he has to be active and territorial.

i had a convict once and when cleaning the tank, he bit my knuckle. he was my fav. fish from that moment on. that sort of fish, ya know.

too bad this tank is small, otherwise id just get a piranha!
 
We have one dwarf puffer in a heavily planted Eclipse 12 and he thinks it's the Taj Mahal.

Stasia
 
piranhas are skittish little wusses.

unless you have like 10 of them and they dont eat for a while.
 
An aggressive tetra? I've read about some on this forum, but can't think of the names (since my tetras are easy going). Like "they're nippy so it's best to have a school of the same type so they spread their aggression among themselves". I've also read somewhere that tetras are related to pirrhanas, but this may be just an assumption since they're all South American fish.
 
Bucktoothed tetras are pretty aggressive, but get up to about 6". A 10gal is too small for a school.
 
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