whats the smallest tank you can use

[amstar]

I have a 16 gallon bowfront tank I would like to use for a single sea-horse. it has a 65 watt 10 k bulb and a 65 blue actinic bulb.

a hang on cpr refigium with 18 watt p/c light for the macro-algae.

the tank will have about 25 -35 pounds of tonga live rock.

can this be used as a home for a sea-horse?

 

[Jillyfish]

seahorses are very social animals, I would not get just one in any tank, but that tank is too small anyway.
I have dwarf seahorses in a five gallon tank, but for most people a sixteen gallon tank is too big for dwarves, and you would not want live rock for them anyway because of hydroids.

Larger seahorses like a tall tank of 24 inches or more.