will I have enough room in my 55g

just them alone...im sure it will work...my tank is over stocked, over planted, and over filtered. Mines a 55gallon and I have 1 pictus about 6" - 1 convict 3" - 3 barbs 3" - 1 pleco 7" - 1 moray eel 18" and thats quite a bit bigger bio load than just 2 pictus cats. Now it depends on what your using for filtration too.
 
Most pictus do not get larger than 5-6". They do like company, do best in groups of 4 or more. That is pretty much all you can put in a 55 (4 of em). You can put some fish toward the top though.
 
right now I have a Crappie,Convict,Pleco,Rainbow Shark,and a 4lined cat in my 55g but I'm gonna get a 75g so I can put the Crappie, and the 4-lined cat and the pleco and the Convict in it and I was gonna put 2pictus cats in their plus some fish that swim near the top
 
Although many say that pictus like groups, I have had good luck with singles and pairs both. If you get one he will be shy at first but usually makes himself at home within a week or two. In a 55 I think a pair would do fine. Remember your four line is a pictus as well, and the spotted variety will act and grow in the same manner as the fish you have. other than the markings, I have seen almost no difference between four lined pictus and spotted pictus. And as brianfl said the seldom get over 6 Inches, I have only seen a couple in my life that topped out around 7. there are also fairly unobtrusive if they have their space and nothing tries to take it.
 
pictus cats are awesome. probably my favorite fish. i had three in my 55g along with a gourami and a few black skirt tetras. everything worked out fine. great fish really active and have a lot of personality but don't put anything on the bottom with them that's smaller than they are because they will eat things like shrimp that stay around the bottom. but hey shrimp are only like 20 cents anyways right?
 
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