My Pleco In Brackish Water

[ikeepfish]

I have a Green Spotted Puffer, a dragon fish (not arrowana), and a 6" Pleco. I have had them living together for a month now and they are all peaceful. I have been reading that the puffer and dragon fish will need to live in Brackish water soon. My question is do I keep all of the fish in freshwater or change the water to brackish carefully. Please leave me your suggestions and a little info on how quick I should add the salt. Thanks for your feedback!

 

[TwoTankAmin]

The puffer is a brackish fish, the pleco is a freshwater fish- they absolutely do not belong in the same tank. I have no clue what you mean by a dragon fish, but if it is a dragon goby it is also brackish an can grow to 15-18 inches.