dead fish

Question
In have 2 55 gal. tanks & 1 75 gal. tank. I was talking with an employee of one of the pet stores in town about Scats. He said they needed brackish water. He also said that all aquariums should have aquarium salt added to the water as it is beneficial to the fish. I did as he suggested & put 4 tsp. of aquarium salt in 1 of my 55 gal. tanks. The next day I found 3 dollar sized angels dead, the day after 1 3" angel was dead & the next day I had 3 ctopoma (spelling?) leopards dead. Two days later my water turned cloudy & has been cloudy for 5 days. I have taken bottom water from each of my other tanks hoping to get the beneficial bacteria from either of these 2 tanks going in the cloudy one, & have done 2 partial water changes. Nothing has cleared up the water. I was told that Stress Zyme would do the trick.  As you might guess, I am extremely upset over this!! The salt was absolutely the only thing that was different from my normal tank care. Can you explain why this happened? I really care about my fish, they are more like pets to me. Thanks for your time. Mauri

Answer
Mauri,
Unfortunately, you were given wrong information. Not all fish can be in salt water all the time. Freshwater fish need fresh water. Most employees that work in fish departments of pet stores no little to nothing about the fish they sell. You found out the hard way. So, the tank that is turning cloudy, is it a new tank? If it is, then the tank is going through the cycle process and that is normal. If the tank is cycling, there should be no fish in the tank for the 6 weeks cycle process. Continue to do water changes to get the salt out of the tank. I use salt only when treating for an illness or a disease. Stress Zyme will not clear the tank water. It will only be one more thing added that is not needed. Let me know if the tank is not cycling and has been running for some time.