Hello all,
My name is Leszek, I am the owner of the aqualed.pl store.
From several days we're seeing increased interest from the shop of your forum.
If you have any questions I'll try to answer.
I noticed that you ask about the width of the lamps. 16 cm is quite enough to illuminate the tank of 50 cm wide.
At this photo we can see the tank 120x50x60H illuminated with 6x39W T5
The T5 lamp was turned on AQL-100/120W, and as you see on next photos, it is quite enough.
If you have more questions, i will try to answer as soon as possible.
greets
Leszek