Are Green spotted & figure 8 Puffers delicate?

I've had 2 Figures die on me within 2 days & the Green spotted lasted me about a week & 1/2, yet all my other fish in the same tank seem to be thriving?

I even added a Cichild & that's doing fine & looking great in the same tank?

 

Those are brackish fish, not freshwater.......

Green spotted puffers can live in full marine I believe.

 

What?!?! Of course they are freshwater that what the store had them in & what I had them in, Yes they do need salt, but are not considered saltwater fish?

What is Full marine vs what? 1/2 marine?

My Green spotted was very happy eatting up any sort of worm I put in there & I was amazed watching it eat worms I thought were too big for him & then suddenly we found him dead?!?!

 

Brackish is part fresh and part salt water. These areas are where rivers meet the oceans and you get a mix of both freshwater and salt water.

Green spotted puffers can live in brackish water, but will also live in full marine, or a full salt water set up.

Both however, need at minimum a salinity level of 1.015

Neither of them is a freshwater fish no matter what the store you got them for told you.

 

OK that explains why these are the only fish that kept dying..

Funny how this store never mentioned this important detail to me!

The guy told me that after they get bigger you should start adding salt to the tank & when you see them getting dark in color its time.

Well the green spotted that lived longer than the rest died today it was dark, seems a bit late to start adding salt!

Trust me I will be talking with them about this.

 

OK that explains why these are the only fish that kept dying..

Funny how this store never mentioned this important detail to me!

The guy told me that after they get bigger you should start adding salt to the tank & when you see them getting dark in color its time.

Well the green spotted that lived longer than the rest died today it was dark, seems a bit late to start adding salt!

Trust me I will be talking with them about this.

Yeah, at my LFS, all the tank label said was "All our Green Spotted Puffers have been properly acclimated to freshwater!" Not a word about how they will need brackish and then eventually marine water conditions.

 

How much & how often would be the right amount of salt would it take to keep these guys healthy?

I do like them.