My husband and I irrigate every day. Usually it is for our allergies, but if it is effective against Covid, all the better. We use the Walgreens wash bottle system. Get the squeeze bottle with packets of salt, etc. to mix in. Use distilled water and heat the bottle in your microwave. (Even room temp distilled water is a shock as our core temp is around 98 degrees) We do 28 seconds. Put the contents of one of the packets into the water bottle, put the straw into the top and close the bottle. Mix it by shaking gently and I always squeeze it a few times to make sure it is worling properly. Good luck! Both of us use this and we haven’t suffered too much for allergies.
My best friend's husband was diagnosed with cancer of the larynx and pharynx several years ago, and has to irrigate with salt water every night.
Yes, I always use distilled water, and nuke it in a Pyrex measuring cup in the microwave. Then into the Hydro Pulse along with the salt, then fire that bad boy up.
I have an older version of this:
https://smile.amazon.com/Grossan-Hydro-Irrigation-System-Original/dp/B000H84D2G