It is NOT Recommended to Mix Seahorse Species
Most people like diversity and for this reason a commonly asked question is can you keep multiple seahorse species together. We do not recommend mixing different seahorse species in the same aquarium. Seahorses from different areas of the world carry different micro fauna (bacteria, ect). Seahorses can have immunity to these and when introduced to another species which has not been previously exposed and with no immunity it can cause stress on the immune system. This can directly cause issues with them and also make the seahorse susceptible to other bacteria or issues that may normally not be harmful. Seahorses have a primitive immune system and are more susceptible to bacterial related issues compared to other fish which likely has to do with why we see this issue when species are mixed.
H. kuda, commonly known as the Spotted seahorse, at our farm. One of the newer seahorse species we are working with.
In short, mixing different species often results in one or both species not doing well. Sometimes issues happen right away and other times it happens months down the road. Some keepers are successful at mixing species but from troubleshooting with hobbyist it seems to rarely go well when mixing species in the same aquarium. Hobbyist often ask us why it matters if all the seahorses are captive bred and from the same farm. We do not mix species at our farm for this same reason. Different species are kept in different systems and therefore they have not been exposed to one another.
Exception-H. Reidi and H. Erectus Can be Kept Together
One exception to mixing species is H. Reidi and H. Erectus. These two species naturally overlap in their distribution. There is evidence these two species naturally hybridize too. We have successfully kept these two species together at our farm for years with no issues. Many other hobbyist have as well and we do not hear of issues when these two species are kept together. H. reidi are a hardy species to keep but their fry are challenging to raise. This species is not as commonly available as H. erectus for this reason.
Brazilian Hippocampus reidi seahorses at our farm
H. erectus, Lined or also know as Saddled Erectus seahorses at our farm.
Mixing Captive Bred Seahorses with Wild Caught Seahorses
We encourage purchasing captive bred seahorses as they are much easier to care for and less likely to have problems. Captive bred seahorses like ours are completely weaned to frozen Mysis shrimp, are use to life in aquarium, are active and healthy. Wild caught seahorses often do not take frozen food, often carry pathogens and overall are more challenging to keep. We realize not everyone is aware of this when first starting out. If you happen to already have wild caught seahorses mixing them with captive bred seahorses could cause issues similar to mixing different species. We do not recommend mixing wild caught seahorses with captive bred seahorses.
We hope you find this article helpful. If you have any questions feel free to reach out to us, we are happy to share our experience and help. Your questions help us improve our content and let us know where we can clarify for others. We appreciate the questions and feedback you may have.
Part of Seahorse Savvy's grow-out facility and farm.