Cae's

[aquaticman1]

around what age or size do they become aggressive?
would this be a problem in my 30 gallon community tank with zebra danios, neon tetras, bamboo shrimp, dwaft gourami

 

[-SPB-]

I think that can vary from each individual fish, and it's surroundings, i'd say from 3 inches upwards, some people say from 6 years upwards. I used to have 3 of them, and 2 were very aggressive towards a red finned shark I had, these were roughly about 3 inches. On the page about them here someone says 5 inches+. They are not suited with flat bodied fish such as silver dollars, angels and gourami's, as it is possible it will latch itself onto the bodies and kill them.