There are many different ways to set up a seahorse tank!  I go through my personal methods, and reasons for them in the following video:

However, if you’re interested in the actually REQUIREMENTS, here they are:


30 gallons minimum per pair, with 20-30 gallons for each additional pair.  Seahorses need territory space, get much larger than you would expect, and have very messy eating habits.  More space means less waste, and more room for swimming!


Avoid crushed coral.  Sand or barebottom


Minimum 10 times turnover.  Much more efficient to have 20 times turnover with combined means.  Please see the explanation in the video @ 10:16


Make sure you have adequate biological AND mechanical filtration to keep organics low in a seahorse tank.


A skimmer and UV sterilizer are extremely helpful as mechanical filters.  Adjustable wave makers and powerheads help avoid buildup and provide needed flow, but be sure to cover them to keep seahorse tails safe!  Whether you use a sump or HOB, go over board on biological media like rock, k1, marinepure bricks and etc to provide many places for good bacteria to live!  Visit the beginner’s corner for more info.


If you need help with cycling and preparing the tank, visit the beginner’s corner, or send a message.  Test kits for a new and cycling seahorse tank should include:  Ammonia, Nitrite, Nitrate, PH, and Alkalinity.  A refractometer is needed to test salinity.  A calcium test kit is valuable for ensuring balance, but optional.


A seahorse tank should be kept under 74 degrees to slow down bad bacteria.  A thermometer is a MUST HAVE for any seahorse tank.  While keeping the temp low will help, even more important is keeping it stable.  Aim for a lower temp, but focus on avoiding temperature swings.  In warmer climates, a chiller will help.  Cooler climates might need a heater, but be sure it’s covered or in a sump.  The true goal is to do whatever you have to in order to make sure temperature doesn’t go up or down drastically and continuously.


Avoid adding any aggressive fish that will either scare the seahorses, hurt them or eat all of the food quickly.  Avoid stinging coral, or any coral sensitive to a seahorse’s tail wrapping abuse.  That disqualifies most LPS and SPS, but there are some exceptions.  Tank mates and coral depend upon the risk tolerance of an individual.  The safe bet is to keep a seahorse only tank, not mixing any other fish or coral.  However, if you choose to mix, merely understand the risks.


A seahorse tank has no real lighting needs (until we learn more about UV lighting and calcium, unless macro or coral are involved, or the light is raising the temperature.  For a macro tank, focus on white lighting in the 3000-6500k range, whereas if coral are in the system, be sure to find a light that will cover their needs without heating up the water.  LEDs work nicely.


A seahorse tank must have ZERO ammonia and nitrites.  Making sure the tank is fully cycled is extremely important.  Salinity of 1.023 has worked best for me, but as always….the importance lies in stability.  Making sure the water doesn’t have any drastic changes is the most important thing.  If you don’t use a freshwater top off, testing and adding freshwater once a day can work, but be sure to also test alkalinity (using buffer if needed).  Speaking of alkalinity, testing PH can be helpful.  Different species are more affected by swinging parameters than others, but keeping things stable is always the best bet!

We might add more to this in the future, but these are the very basic guidelines.  Be sure to join the site for access to the forums and ability to ask questions and/or share your experiences with seahorses, pipefish, coral, macros and tanks.