: For a single pair of large seahorses, a 30-gallon minimum is standard, with an additional 15 gallons for every subsequent pair.

Maintaining a thriving seahorse environment involves several non-negotiable technical requirements:

: The tank must include "hitching posts"—structures like live rock or artificial sea fans—where they can anchor themselves with their prehensile tails.

: Stability is key. Temperature should stay between 23–26°C (73–79°F), and ammonia and nitrite must be kept at zero. The right tank | Seahorse.com