Yellow Seahorse, Hippocampus erectus. We sometimes find yellow ones but they are very uncommon. We know they will go very fast.
These are wild caught seahorses and although they have been kept in a medicated system for about two weeks, it’s always a good idea for you to quarantine them for another two weeks prior to adding them to an established system. Seahorses require live foods such as enriched live adult brine shrimp, live mysis shrimp, live grass shrimp, or any other small live fish or shrimp. We try to get them started on eating frozen mysis shrimp. If you have trouble getting them to eat the frozen mysis shrimp, try feeding them enriched live adult brine shrimp or grass shrimp for a few days and then try weaning them off the live food and onto the frozen food. They will not thrive on just live brine shrimp and will eventually waste away unless you are enriching the shrimp right before you feed them to the horses.
Seahorses are reef safe to a point. They generally will not bother other fish or invertebrates, but may go after very small fish or small shrimp. They are not aggressive feeders, so they require extra care in a tank that has active fish (most people would not recommend mixing them with fish because they are such passive feeders.) Seahorses should not be put in tanks that have sea anemones, corals, or zoanthids because they can sting the horses and the anemones may even eat them. Mushroom and leather “corals” are OK, as are gorgonians.
Seahorses are not for the beginners because of their picky feeding requirements, so this shouldn’t be your first fish.
For more information about aquarium requirements, caring for and raising seahorses please visit http://www.seahorse.org, a dedicated seahorse forum