I stop using salt by the late 80's. Softwater fish like tetra and cory's do not like salt and it can irritate them. Plants also don't do well and will suffer depending on how much salt is in the water. Some plants can be slowly acclimated to accept some salt (brackish tanks) but overall it's just not good for them. That is one of the reasons people who have water softner units have to use RO
water... in these units calcium and magnesium ions (both of which plants use as macro nutrients) are exchanged for sodium ions. I had a friend who kept losing fish and who's plants were doing horribly. After much talking I asked if he had a water softner on his house. Yes he did and once he quit using the water from it his fish and plants took off.