Monsters for my 55

[mikec707]

You could keep 1 or 2 Gulpers by them selves.

 

[tomojsg]

You can try a few Florida Gars, Black Ghost Knife Fish, Elephant Nose, Fire Eel, Wolf Fish, Depending where you live and how much you are willing to spend, maybe even a few smaller Piranhas.

:WTF:

 

[$INI$T3R]

Get some guppies!!! Their alot of fun!!!

 

[Nighttouch]

Here, this oughta help: http://www.monsterfishkeepers.com/forums/showthread.php?t=227845

 

[davdev]

Try a Green Sunfish. Colorfull hardy, native fish, that can be very agressive, yet remain small enough for a 55. Added benefit is you don't need a heater

 

[619aquaponics]

Already have some in another tank and love em

 

[619aquaponics]

Do you want something that's fairly active, or are you fine with something that is more sedentary? Do you want something more colorful, or more drab? Something that is very owner-responsive? Help us narrow it down a bit...

Just a few I would consider....
Red wolf fish
smaller species of puffer
Green sunfish

I'm mostly in to natives, and there are quite a few that would fit what your looking for, it kinda depends on what's available to you locally though.

Owner responsive is preferable. It doesn't have to be colorful but I would like it to at least have a nice pattern. A puffer would be cool but are there any decent sized FW puffers

 

[Younglin]

Sculpin

 

[steech420]

I heard Killi fish can be very colorful... not sure if they are preds though.
otherwise maybe a fahaka puffer they pretty kew.

 

[Younglin]

otherwise maybe a fahaka puffer they pretty kew.

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