Hey there and welcome to the forum!
Morton’s salt has anti-caking agents added to the mixture, hence their famous jingle, [I]“When it rains, it pours!”[/I] For the neti to be therapeutic, you need a pure salt, like you have been recommended to use by David and IA. My bet is the neti pot saline packets are just this. In addition to those packets, you should be able to buy this pure salt in your grocery–look in the salt aisle for sea salts, Himalayan salts and the like. I can buy in bulk like IA has recommended in my natural grocery, so look there if you also have that option because it will cost very little this way.
To make the solution to the salinity that is good for you, taste it before you pour in your nose. It should taste just a tad salty–like your own tears. Using well water or purified or filtered water will help with irritation too. I have a problem with my city’s water, so I use the water run through my PUR faucet filter to remove the chlorine.
There are many threads on this forum about the neti and using a variety of salts and even honey–do a search to find those goodies.
I have read your other posts, and wanted to tell to you that since you are navigating your newly diagnosed, obstruct apnea, be sure to add that information to these satellite posts as well. It is a really important piece of your personal puzzle and will help you get better recommendations from the members who are sharing with you. You should also know that you will have specific issues related to using the neti resulting from your obstruction. Now that Oprah and Dr. Oz have made the neti pot famous as the “nose bidet,” it is likely your own primary care physician will be able to help you to utilize it for your condition.
Willem has offered you some very sound advice on one of your other threads–look up Hamsa at Stone Yoga or Bonnie AmarJyothi Pariser at http://www.yoga-loka.com/ for highly skilled and trained Yoga therapists in your area.
All happiness,
Nichole