A few issues

[Amorvo1]

I did think the ram was rather grumpy like my hubby

[Staffylover]

The Ich parasite needs to be bought in with fish so if this is a new issue but no new fish have been added in the last 3wks it's very unlikely to be Ich, agree with the others fish in the pics looks to have a fungus, often caused initially by injury, hope the meds help the little guy.

[PaulVerrall]

I thought ich can lay dormant in a tank for long periods, when a fish becomes stressed and immune system lowers it can attack

[plankton]

Ich is a really strange phenomena....
If the original fish bring it in but are immune to it then it can be present for long periods (unless there are 14 days with no possible hosts).
If they don't, or you've got rid of it with treatment, then if it appears then it has been brought in with new stock.
(and that's a precis )

[Staffylover]

I am certainly no expert but have done a lot of reading on this recently, it seems the idea that it can lay dormant in a tropical tank for long periods has been disproven which is a least a bit reassuring, although it would be possible to have such a low rate of infection that it does not become obvious at least in the short term, the main reasons given for this are 1. the explosive reproduction rate when in the tomont stage 2. temperature, at tropical temperatures the entire lifecycle takes roughly two weeks. 3. It's an obligate parasite it cannot survive without live fish to complete the life cycle, here is a link to one of the articles it's a bit heavy going but is more in depth than most,

https://edis.ifas.ufl.edu/publication/FA006

I think in cold water situations it would be much more difficult due to the longer life cycle so at least we have that in our favor