Saltwater Amphipods & Copepods -1000 Pods - Get 2 for 1 The type of copepods we have are benthic - which is great for a refugium or tank with live rock. Amphipods can be distinguished from copepods as able to seen at a distance. Amphipods range in size from 5-10mm, where as copepods range from 1-3mm. This listing is for a variety of both. Amphipods and copepods make excellent food for picky eaters like seahorses. Mandarin gobies love th