. . . Salt is a decent treatment for many common fish ailments but is not for everyday use.
Penicillin is great for many people diseases but I don't take a daily dose of it to help me lead a healthier life. Instead I try to keep things clean and myself well fed. Much the same applies to fish. Keep their water clean and the fish well fed as a disease preventive.
If you are using RO water-definately yes.
As BettaFishMommy said, freshwater fish like fresh water, not salty water. Salt is a decent treatment for many common fish ailments but is not for everyday use.
Penicillin is great for many people diseases but I don't take a daily dose of it to help me lead a healthier life. Instead I try to keep things clean and myself well fed. Much the same applies to fish. Keep their water clean and the fish well fed as a disease preventive.
The use of salt in freshwater as a general tonic is an old recommendation that will never die. This topic has been beaten to death.
Salt is not required to successfully keep freshwater fish.
I went through this same dilemma at one point. When I started an LFS employee told me to always keep salt in the tank. So I bought a box of aquarium salt from him. I followed the instructions and always added salt with water changes. Eventually I had fish die, including a pleco, and some of the advice I got (here) indicated I should stop using salt as a regular additive.
I've now got five tanks running without salt and all of the fish SEEM perfectly happy. So as far as anecdotal evidence, there you go. Unfortunately I find that you'll never get a consensus on this sort of thing. I think in nature there IS some tiny amount of salt in freshwater. For whatever that's worth.
The use of salt in freshwater as a general tonic is an old recommendation that will never die. This topic has been beaten to death.
Salt is not required to successfully keep freshwater fish.
Also, do not use iodized salt. the iodine is not good for the fish- even though it is more expensive, use aquarium salt. Like I said though, I use very little salt, but I do believe that a little is good for the fish-but it is your tank and your fish, so it is all up to you!