Im a pictus keeper. Depends what pictus you are talking about. I do not have spotted pictus anymore but I know at adult size they looks just the same as when you buy them, if you get them at normal size, sometimes I see small babies, their faces just change a little is all, eyes dont seem as big. They usually stop 4-5", I have yet to see one hit 6" as they claim they can get. They stay pretty small.
On the other hand I have a white pim and a spotted pim. When I first brought them home they looked just like a spotted pictus but darker in color, more gold instead of silver.
They are pretty much done growing. Spotted Pim is 6-7" the white pim is 6" Their heads just got more wider and the whiskers are so long lol
Oh btw when these guys growl it is something else. Sounds like a low dog growl and if you have them in a bucket or something holding it, you can feel it vibrate. I felt spotted pictus growl and vibrate a bowl they were 3 and 4" these two pims of mine when I had them in that bucket and moved them it was loud and vibrated the bucket. I can hear it at times at night as I sit by the tank at my computer.
Top view
A few other pics, second one she is behind the vampire pleco hiding LOL