For 30-gallon tank
2 Sea anemones (Condylactus, Calliactis, Bunodactis, Ceriantheopsis, species as available).
2 Starfish (Echinaster/ Luidia/ Astropecten)
4 Brittlestars (Ophioderma)
2 Sea urchins (Arbacia/ Lytechinus)
1 Colorful and hardy sponge (Axinella/ Xestospongia/ Cliona)
1 Sea whip (Leptogorgia)
4 Living shells or rocks (Chitons/ Feather Duster Worms/ Serpulids/ Boring Sponges/ etc.)
2 Hermit crabs (Clibanarius/ Pagurus)
4 Snails (Cantharus/ Nassarius)
1 Algae
2 Sea Cucumbers (Pentacta/ Thyonella)