I have 2 figure 8 puffers. To make the water brackish, I add 1tbsp. of marine salt per gallon. When you do water changes, just add accordingly depending on the amount of gallons you are replacing. I have not had success adding real plants to the tank, so they are silk. I do have two giant Marimo moss balls that are doing really well. I also have ghost shrimp in the tank. They keep it clean and serve as the occasional snack. Other than the added marine salt, it is no different from my freshwater tanks.
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