I currently have a trio in my 16 gallon. But I bought them all at the same time as well as they "grew up" together. They get along great....although there is the occasion disagreement about who's bloodworm that was.
When adding the new puffer you might want to rearrange the decor in your tank so that the old puffer "feels" like it a new tank and won't be as territorial.
Here is a statement made by a member (Lotus) on the dwarf puffer forum:
I just added to young males to a tank with a lone older female with no problems.
Perhaps with a male you will need to rearrange the tank, or take him out temporarily, add her, then add him back so he doesn't consider it "his" tank when he is added back.
Mine is definately a she, and living in a 40 gallon 'community' tank. I've had dwarf freshwater puffers several times over the years and never had problems with fin nipping that others talk about. Perhaps because I have heavily planted tanks, there is lots to break the line of sight? Not sure, but so far so good.
I think I'll be on the lookout for a young male. If it doesn't work out, all the more reason for another tank, yes?
Just goes to show you can't believe everything on the web.
30 gallon minimum for a dwarf puffer?
And its Carinotetraodon travancoricus, not Tetraodon travancoricus as they call them.
No mention of their favorite food: snails.
I must have always lucked out and gotten mild-mannered puffers (or Fresh Puffs as I call them). I've never had them bother other fish. My female currently lives with dwarf rasbora, a Badis species, even red cherry shrimp. She doesn't seem to notice any of them.
But don't let a snail sneak around too long! I had a snail creaping along the glass with two shrimp hitching a ride (they were all eating algae on the back wall of the tank). The puffer went right after the snail, ignoring the shrimp, who continued to eat as if nothing was going on (like the snail being pulled from the shell).
A friend randomly bought me some puffer fish from walmart. thing was the devil in my tank. ended up giving him to someone else. he was bright green with black spots looked awesome. Lol just my two cents I think they are so cool looking tho.
I kept puffers for several years (that was me on the Dwarf Puffer Forum). I never had problems with them in a puffer-only tank. Most of the ones I had I bought in twos or threes when they were tiny. I think 30 g is excessive. I kept two to three in a 7 g tank. I know that's considered "pushing it" but I didn't have problems. I always did weekly water changes of 50 percent and because I only fed bloodworms once a day, there was never any excess food in the tank to make water quality bad. It was a planted tank, too.
I probably wouldn't keep them in a community tank if I wanted to feed them bloodworms. They tend to be a lot slower than other fish at getting to the food (they like to watch the worms for a few seconds before they pounce), but it might work if you have plenty of snails to feed.
My last puffer died about six months ago and I decided to break down the tank and have no puffers for a while. I miss them.
I probably wouldn't keep them in a community tank if I wanted to feed them bloodworms. They tend to be a lot slower than other fish at getting to the food (they like to watch the worms for a few seconds before they pounce)
I thaw a chunk of bloodworms in a small cup of tank water, and then spot feed my dwarf puffer with a worm baster (dedicated turkey baster).
Its funny, they do eat slower than a lot of fish, but the other fish come to the sides of the turkey baster and 'peck' at the clear tube where they can see the bloodworms. It is only the puffer that will go to the tip of the baster and wait for them to drop out. I just gently squeeze the bulb until a few stick out of the tip of the baster. She will grab what she wants (usually 4 or 5) then scoots off to hide in the plants and eat alone. I watch where she goes, and feed the rest of the bloodworms in a different area of the tank. Has always worked well for me.
Well, a trip to the only LFS I trust to buy fish yeilded a young dwarf puffer, but too young to tell its gender. If I get any more puffers for my tank, I think I want a male and one or two females to keep with my current female. I told them I'd be interested if they would let me know the next time the got a group in. They said this one was received in a bag of unrelated fish that they didn't even order.
On the plus size, I gave them a bucket of red cherry shrimp that they paid $0.50 each store credit. So now I have $35.50 to spend next time I go in.
For three years, I bred them and sold them to my LFS in Iowa. They were kept in a 10 gallon species tank then. When I moved to Texas, I only kept 5 female and 3 males (the females were all berried). Since April, they have lived in a 40gallon breeder planted tank. I don't know how many are left, but I know there are 3 berried females that I put back when I took the rest to the LFS. I'd guess there are 4 or 5 other sub-adults and some juvies hiding in the plants. I had thought the fish would keep their numbers more in check, but they are breeding outa control! They talked me out of my 'black' red cherry shrimp female too. She had dropped her latest brood, so I'm sure some of her offspring are hiding in the plants.