Figure 8's are great puffers and if you are to keep one you won't be disappointed. They may survive in a freshwater setup but not thrive. It will live only for a short time in this enviroment. Just because something can survive in it doesn't mean it should be kept in it. If you can't create the correct enviroment for these amazing fish, you don't deserve to have one (same for any pet, fish or otherwise). They need a brackish enviroment, hard alkaline water. Foods should be Shrimp, cockles, muscles, mysis and snails. They will accept other foods but if it isn't tough or crunchy the puffers beak will get to large causing starvation and death. Foods should be supplied daily to avoid aggression (not neccessary if kept as a species only with one specimen or more if tank is large enough). However they do get more aggressive as they mature especially at mating time. This should be considered if you keep them with other fish as you will either need another tank to separate them or watch as your puffer eats his way through the population! Most stressful! If you search, you will find loads of info on these fish, some contradicting but this is mainly from people who are inexperienced and haven't researched before posting up web pages. My advice before purchasing one of these is research. Then research more. Join a mailing list or forum. These are the best sources of information. Aqualog has a 'Puffers' book. [Editor's Note: Fishbase.org lists Tetraodon biocellatus as a true freshwater species - MA]
I've had a figure 8 Puffer for about 3 months now. It is the coolest fish in my tank.I have 1 Pleco, 4 neon tetras, 5 Red eye tetras, 4 cherry barbs, 4 green tiger barbs, and one fiddler crab.He gets along with all of those fish. At first he was really curious about the crab. Now he seems to just leave her alone and fallow me with a big smile begging for food.He eats almost everything but loves snails.I was amazed when i went to the pet store to get him because all of the employees thought he was marine or brackish but in fact he is fresh but likes brackish just as well.
My figure eight pufferfish is not aggressive at all. He keeps to himself and mostly stays behind a plant in the back corner of the tank. I noticed that he uses his tail to steer, but uses his other fins to propel himself through the water. He reminds me of a bumblebee and that's why he caught my attention at the pet store, I thought he was a tadpole at first! He investigates everything in his tank but is usually hiding behind his plant.
I've had my figure eight puffer (Leo) for 6 months now and he is still the best fish in the tank. I would say figure eight's are the most peaceful of the puffers, I even keep mine with guppies (they were meant to be a snack!) and they manage to push him away at feeding time! At first shy, now Leo follows me all around the tank while I'm carrying out maintenance work, but be careful of their little teeth, they are suprisingly sharp and strong. Also watch your nails, Leo likes nibbling mine if my hands are in the tank and has managed to chip a few! Also remember to feed snails to keep their teeth trimmed down. Enjoy!
These fish are brackish! They can live in fresh, but are much more likely to become sick. It is a great fish and it's a shame to see them get sick from being in the wrong water. In brackish I have heard of them living 12 years or more, this may be rare, but still...
I've had a 3 cm F-8 puffer in a 40 L tank with a pair of mollies (in brackish water) for 4 months now and she is the most peaceful fish you can find! The mollies are bigger than her, so I thought that could be the reason she hasn't been aggressive, but they just had babies and she didn't even touch the fry! When I first got her, all her fins were nipped from being with other fig 8's in my LFS, but a week of melafix and all that was healed. Everyone who sees my puffer gets obsessed with her. She eats from my hand, and if I hold a snail above the water, she jumps up to get it! Sometimes, just for fun, I distract her and sneak in a couple of snails in the tank and after a couple of minutes, she smells them and all of a sudden you hear the sound of their shells crushing! I have a 10 L snail breeding tank too, which I recommend to people who have puffers, it's very easy to grow your own. If you want to keep them with other fish though, I recommend not getting any fig 8. You should watch their behaviour closely in the LFS before you get them, they all have their individual personalities. Some of them are very nippy, but you can totally tell if you just watch them for a while. I went to my LFS three times before I decided to get this one, mine never attacked any other ones, although she was as big as most of them.