amazon sword sizing

I have a few swords that I bought quite a while back, nicely large leafed,
etc. The shouts have sprouted off, and I've snipped months ago, but they're
growing different to the parent plants. They're more shrubby. One plant has
20-30 leaves and only 4" high. Do I have to prune leaves to get the others
to grow larger? I use a standard aquarium .15-0-0 enriched fertilizer. (BTW,
how often is a person supposed to add the fertilizer?)

Also, how much light do they need? I currently give them 6-10 hours
power-glo lighting, 6 or so hours darkness, the rest of lighting comes from
indirect sunlight, ambiant from room lighting.

Thanks.