I am not a fan of using salt as many fish cannot tolerate it. Loaches being one, along with all catfish and characins.
My cure for ich (which I have had more often than someone with my experience should) is now Coppersafe. The last time I used this, with loaches, the ich was dealt with and the loaches appeared none the worse.
If you go this route, I would first do a major water change, 75-80%. Then dose with Coppersafe; you only need use it once, it lasts 30 days (except water changes will obviously dilute it, which is one reason I suggest a major wc first, the other is to dilute the salt and Jungle stuff). You can raise the temperature if the fish can manage. The fish you mention are OK with temps over 80F for a week, so as long as there is not something else that will have problems with a high temp, I would raise it because loaches with ich can be very difficult to cure, sometimes impossible. Slowly raise the temp, just turn up the heater today and then again tomorrow, aiming for 84F for the rest of the week. This helps to speed up the ich cycle.
Some people advocate high temperatures, meaning 90F, on its own. I've not tried this. If you do this method, make sure there is plenty of water flow and surface disturbance to bring oxygen into the water. At higher temperatures, water can hold less oxygen, much less.
While I'm here, a comment on the possible cause. It may have come in with snails/water. But healthy fish usually can fend this off, it is natural; ich occurs in all tropical waters in nature but the fish manage to combat it. Stress, whatever the cause, is a major reason fish come down with ich.
And you have some fish issues causing stress. Clown loaches are very social fish (all loaches are for that matter). They should always be in a group of 5 or more. A lone loach is highly stressed because his "family" is not present, and he feels isolated, and vulnerable. This alone could easily bring on ich.
Same for the
Tiger Barb. This species should always be in groups of no less than 8. They have a strong "pecking order" within the group. Fish that are shoaling by nature and kept in too small a group will not only suffer stress and health issues but frequently become even more aggressive than normal.
Always research fish before acquiring them, so you will know how many they need to be, tank size, compatibility issues, etc. We have fish profiles, second tab from the left in the blue bar across the top of the page.
Hope this helps you.
Byron.