Marine tanks use the same nitrogen cycle as freshwater, plus mixed salt, stable specific gravity, and usually live rock or a dedicated biological filter. Captive-bred clownfish are a reasonable first marine fish. Yellow tangs are not a nano-reef impulse buy.
Cycle first — how to cycle a fish tank applies here too. Test salinity as well as ammonia. A tight lid matters for jumpers such as firefish gobies.
Saltwater · Intermediate
Amphiprion ocellaris
Ocellaris clownfish are among the more forgiving marine fish — but they still need a cycled saltwater tank, stable salinity, and marine-level testing. A 20-gallon tank can house a pair; 30 gallons is more comfortable.
Min. tank: 20 gal
Care notes →
Saltwater · Intermediate
Zebrasoma flavescens
Yellow tangs are active Hawaiian surgeonfish that need swimming room, not a nano reef. A conservative home-aquarium minimum is about 125 gallons with length to patrol and rock to graze.
Min. tank: 125 gal
Care notes →
Saltwater · Intermediate
Nemateleotris magnifica
Firefish gobies are elegant, hovering dartfish for a covered saltwater tank. A 20-gallon reef can work for one; the lid is not optional — they jump.
Min. tank: 20 gal
Care notes →