20 gallon lacking "wow factor"

[Lampshade]

ISO will do it too, there's a good write up on here somewhere about what setting to use if you have a DSLR, can't find the link right now though. ISO setttings change your Fstop though, so you will have a faster/slower shutter because of it.

here's my bookmark for re-remembering what each does:
http://beej.us/guide/bgp/sfi.html