I'm setting up a 6 gallon for shrimp only. I'm planning on either the blue pearl or yellow shrimp. I have a black background, and wanted to go with either black sand or Eco-complete which is black. I can't find either at any of the LFS around here or at Petsmart. I have a bag of black aquarium gravel (Top Fin brand). Will that be okay? Do the shrimp thrive best in any particular kind of substrate? For plants I plan on using vals, pennywort, hornwort, java moss, and a couple of crypts.