i've not got photoshop nor the ability to learn it in any reasonable amount of time, so i'm just going to present the banners i like the best and think have some really great aspects.
my absolute favorite; c'mon, who doesn't love seeing a pleco on the glass? but the right-hand corner feels unbalanced.
i think that if the coral reef picture from this banner was flipped and put on the previous banner...
very soothing and a great picture choice, but again, the right-hand side needs some depth
perfectly understated; very minimalistic and well, if beige was an emotion this would project it. a very balanced composition.
love the freshies on the left! a little heavy on the white-space, but a quick fix would to increase the text size.
so in no particular order, those are the banners i liked best and what i liked about them!