Help with Tank chemistry

I have the Emperor 400 Bio-Wheel Power Filter with Carbon Filter, Aqueon Circulation Pump 500. My salt level is running at 1022 and I was told that was good for the 5 fish I have. Some say 1026. I have sand and coral rock and live rock. Introducing more live rock as I removed some of my live rock to clean it not knowing that I wasn't supposed to do that unless I used aquarium water. Didn't know I was killing good bacteria. I am on well water with no filter. Some say to boil it first others say not to. Last water change I purchased 10 gal. salt water from the Pacific at Petco. My nitrate level went down at last water change and am hoping it will lower again when I do my next change on Tues. of next week. I will be purchasing more salt water instead of mixing but that really gets expensive! I introduced new fish to my tank 3 weeks ago and lost my 4 yr. old wrasse, a clown and a my new anemone. I was told my salt level was too low . I had misinterpreted advise at previous 25% water change and didn't add any salt so my level was at 1016. I slowly brought it back up over a 5 day period. This is why I joined this forum as store workers can often be too busy to spend any amount of time giving advise and often really do not listen to what you are saying because there are so many interruptions by other customers or telephones. I have had them grab fresh water things off the shelf for me to use and when I repeat that I have a salt water tank then they are like "nope you can't use that". Often the stores are out of stock on items I need like salt water. I had to drive 60 miles just to get water last week. Sometimes I feel like they are trying to make the sale and get me out of there. Some have been helpful and take the extra time but I find myself questioning their experience. I make it a point to speak to staff that has salt water tanks themselves.