fresh water aquarum

Question
My friend has a mixed tank of fish 900mm x 480mm x 380mm containing silver dollar,molly,glass fish,bala shark and one or two other. She has added a green spotted puffer. What should be the correct amount of coarse salt added to this tank. Please give measurements in table spoon size to be added.

Answer
Hi Jannie,
Pufferfish are brackish water and all the other fish you have listed are freshwater fish. Therefore, these fish have two different requirements. They shoulden't be mixed together as puffers are very aggressive and they have different water requirements. They can survive in freshwater but they will not thrive and will eventually die so it is considered cruel and selfish to keep them in freshwater tanks. I do not know a lot about brackish water fish although you need a hygrometer to measure the salinity.

Regards,
Chloe.