It will be. It is my first brackish tank though...so I am a bit in the dark. Right now I have the salinity around 1.000 or less (my hydrometer only goes to 1.000). I am working it up to 1.010 for the gobies. I am also transitioning slower due to acclimatizing the plants. Right now I have guppy grass, java ferns, anubia, and wysteria...all of which are said to be brackish water adaptable. All the plants are doing great so far...no browning or anything. I am going to keep it at 1.000 until the puffers get out of quarantine and then bring it to 1.005 and then 1.010.
The Indian puffers are actually completely freshwater but can live in brackish while the gobies are brackish and this species, Brachygobius xanthozona, are adaptable to freshwater. The problem is that by staying in freshwater the gobies lifespan, which is already fairly short ~2 years is shortened. I have not read the same for indian dwarf puffers and brackish water. I am compromising on the water salinity for the sake of the gobies.
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