I know it's bad. I had been keeping Africans in a 55 gal but recently a disaster wiped out all my tank save one mature female morrii that seems very unhappy since her tankmates of four years have died. oh and the pleco survived as well. I have crushed coral in the bottom of the tank with built up limestone caves so the water is hard and the ph is high - not 8 though. Today I went to the pet shop intending to get some electric yellows but my son found a spotted puffer. From what I knew of them I thought it might be fine in a less aggressive african tank such as i like to keep with a little more freshwater salt that I usually use. But the more I've read up the more I think I need to go totally brackish for this species... is that right? I mean do I have to use the marine salt and all? I like him but I've always kept africans, is there a happy medium of water conditions that I can keep both africans and the puffer. If not then I might go totally brackish but I don't see many cool brackish species that can be kept with puffers and won't outgrow a 55. Can you all just list the species that you have successfully kept with puffers over a long period and also the water conditions that you have kept them happy in over long periods. I might just get some rays and get rid of my last african and pleco but I would be sad to see them go...

spotted puffers start out fresh but become brackish throughout there whole life and are full marine when fully grown. i wouldn't recommend mixing them...

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I'm so sorry I haven't been on the forum in so long! Don't worry, I haven't forgotten this lovely website! I moved to a different county back in May 2011 and started high school in a totally different school district. So I'm still adjusting and studying hard, and don't presently have any aquariums. But once I do, I'll be right back on this forum!

yeah thats what i've been reading.

but I've been reading different views as well:

Green Spotted Puffer
Tetradon nigroviridis
Green puffers are commonly described as freshwater fish, but in actuality, they thrive in brackish water. This means they require at least one tablespoon of salt (aquarium salt, with marine salt being better) per 5 gallons of water. To be exact, they require a specific gravity of 1.005 to 1.008. ....





African tank:

Setting up an african lake aquarium


..... For every 5 gallons of water, add 1-tablespoon Epsom slats, 1-teaspoon baking soda, and 1-teaspoon aquarium salt.


...

also this:
note the specific gravity is within the range of that recommended above for spotted puffers:

Best Answer - Chosen by Voters
8.2 will be good for the pH as most african cichlids prefer between 7.8 and 8.4. Startzime won't really do any good for nitrates you will need to do a water change to get them down (though anything under 40ppm is considered safe, the lower the better) Depending you the species you are keeping the specific gravity (measure of salinity) should be between 1.005 and 1.010 .....


The water requirements seem to be pretty similar to me. If a fish can tolerate fresh, brackish and salt during it's life it's well... tolerant to different salinty. one thing everyone agrees on is that they need really clean water.

Green spotted puffers need brackish water then eventually almost full marine. They need marine salt NOT aquarium salt. They are also kept best alone as they can be very aggressive. But fun little guys!

You may be able to keep them in the same tank. Just remember green spotted puffers are very needy fish. They are also very dirty fish and like everyone else has said they are very aggressive. Like i said you may be be able to but no guarantees

Also like everyone else has said they are a brackish fish not freshwater. I have mine in a salinity of 1.013 and he is the only one in the tank. Also not to mention you will want to do at least a 20% water change weekly.