Tank Mates

Due to the unusual salt requirements of the Green Spotted Puffer, and their aggression, tank mates must be chosen carefully. Green Spotted Puffers are not a shoaling fish and do not need the company of other fish to keep them happy. With careful planning and enough tank space there are a few fish that can successfully co-exist with GSPs.
Since Green Spotted Puffers can only handle freshwater for a short amount of time it is best to avoid housing them with any freshwater fish. Freshwater fish, like cichlids and barbs, can only handle very small amounts of the marine salt vital to keeping the Green Spotted Puffer healthy. It is highly advised against to house a GSP with freshwater fish for any amount of time.
The problem with housing Green Spotted Puffers with low-end brackish fish is similar to the problems with housing them with freshwater fish; they can only be housed together for a short amount of time. There are few brackish fish that are readily available to the public. Violet Dragon Gobies are becoming more popular in the aquarium trade, but because of their tendency to lay still on the bottom of the tank they make a tempting meal for a GSP. The smaller Figure Eight Puffer has been successfully housed with Green Spotted Puffers for short amounts of time, but because of the difference in s.g. they need to thrive they cannot be housed together long term. Scats and Archer fish could potentially be good short-term tank mates, but again, could not be housed with GSPs long-term due to differences in s.g. needed to thrive. Mollies can potentially be housed with GSPs long-term, but many people report that mollies will follow a GSP around the tank and cause unneeded stress on it. Gobies do not make good tank mates and almost always end up as a meal. Other puffers with similar s.g. needs, such as Ceylons or other GSPs make good tankmates assuming there is enough room for them to live comfortably (30gallons per GSP and 40gallons per Ceylon).
Full grown Green Spotted Puffers thrive in full marine conditions. Once a GSP is in a tank with an s.g. of about 1.021 other marine fish can be added to the tank, along with liverock and certain bad-tasting corals. Clownfish seem to make excellent tankmates, I personally keep my Green Spotted Puffer with a False Percula Clownfish. True Percula clownfish are more aggressive than False Perculas, but could potentially do well with a GSP. Maroon Clownfish tend to be too aggressive for GSPs, while Tomato clowns seem to be okay. Fast moving small fish, such as damsels and wrasse do very well. Slower fish can be attempted as long as there are a lot of hiding places for them.
Before considering tank mates for a Green Spotted Puffer make sure you have enough space for them. Keeping fish in a tank that is too small for them could result in stunting, high levels of aggression, and dangerous water parameters. Leave 30gallons for the Green Spotted Puffer, and then make sure to research whatever fish you intend to get and give it enough space too.
If you choose to get tank mates for your puffer be prepared for the worst. Puffers are very aggressive and have been known to kill a tank mate it had co-existed with for months, or even years. Every puffer has an individual personality and what may work for one person could end in disaster for another.


Thank you to those at The Puffer Forum who helped me write this article and shared your tank mate experiences with me.