If you want to keep seahorses, it is my firm belief that you owe
them the best environment you can possibly provide. When choosing
equipment, tank mates, or any other aspect of the seahorse home don't
ask what is required or possible for their survival but, rather, ask what is optimum for
the seahorses and their long term wellbeing.
Seahorses are slow eaters and should not have to compete for their
food. In addition, seahorses are easily stressed by fast moving or
aggressive fish. For these reasons, a species only tank is highly
recommended. Personally, my seahorses have only clean-up crew and
one scooter blenny as tankmates. I do keep a variety of soft
corals with them. Most seahorse keepers will
someday give in to the urge for more fish or corals in the tank...
please be cautious in doing this and read this excellent
article on tankmates.
The information here is not appropriate for dwarf seahorses (H.
zosterae). If you are interested, please visit our
Dwarf page. I would also suggest you
visit Seahorse.org and
Syngnathid.org for information
on their specific needs.
First, you will need a glass box. A tank. Unless you are
keeping H. zosterae it is recommended that you have at least a 20 gallon
"tall" tank. I recommend that you get the best
tank you can afford. Compared to the amount of money you will be
spending, the tank cost is a minor matter.
The tank will be filled with either natural seawater or artificial
seawater which can be purchased at your LFS (local fish store) either
premixed or as dry salt mix. If you are using artificial seawater,
you will need a source of filtered water. When you mix saltwater
it must be allowed to aerate and age overnight before adding to the tank
to be sure that the salt crystals have completely dissolved.
The tank must be cycled and preferably be a mature tank. The
inhabitants of your tank will create toxic ammonia as a waste product.
There are bacteria that convert the ammonia to nitrite and then to
nitrate which is less toxic. BEFORE any living creatures are added
to a tank, it is necessary to establish sufficient colonies of these
bacteria - this is called cycling the tank. There are articles on
how to property cycle your tank at
Seahorse.org and at
You will need a salinity meter to measure the salt content of the
water. You will also need equipment or tests to monitor PH,
ammonia, nitrite, and nitrate. Be sure all tests used are
appropriate for saltwater.
Seahorses do not have any specific needs for lighting.
Florescent lights should be full spectrum to simulate daylight. If
your tank has very bright lights, be sure to provide shadier areas as
All living things require oxygen so it is important to use an air
pump and airline (without airstones) unless your system includes another method of
oxygenating the water.
It is recommended that water circulation should be 2-4X your tank capacity.
IME most seahorses actually enjoy having areas of
moderate current as long as calmer areas are also provided.
Stable water temperatures are also very important and you will need
to provide a heater and/or chiller depending on the
needs of your species and your local
To keep the water clean you will need to provide filtration.
Mechanical filtration removes particles from the water. Biological
filtration is the removal of toxins as performed by nitrifying bacteria
as mentioned above. Chemical filtration is also used under certain
circumstances. Plants and macroalgae also aid in the
removal of excess nutrients from the water.