[Enigma]

In the end, you need to decide what is right for you.

You've pretty much reached your stocking limit for fish. You could maybe add another little fish, or a couple of really little fish. In the event you do not eradicate ich from your display, you risk infecting any new fish you add. If you won't be adding any new fish, that isn't an issue.

You could let the fish fight it off. Many fish do this successfully. In the event something stressful were to happen, the fish could weaken and become susceptible to the ich again. But, If you upgrade to a larger system and move your fish into it, they're going to bring the ich into the new system.

Garlic is really your only option for treating in your display with the other livestock you have, and anecdotal evidence does support the treatment for boosting the immunity of fish to ich.

So, can you live with ich in your system? That's for you to decide for yourself. No one else can (or should) do that for you. And, (while this may sound callous) you don't have any rare or overly costly fish in there: they could be replaced quite easily if they all died from it.