Are Tetras Resistant To Meds?

[smudge_]

nah the point with this tank was to get a small, easily kept tank.  So I don't have any other tanks sitting around
 
im really depressed that this has happened after I spent ages doing a careful fishless cycle, getting the right fish etc.
 
Also, I am deeply confused why between 10 corys, they don't have one spot between them when the tetras (who brought the white spot) have been decimated and the fighter looks like that ^

 

[eaglesaquarium]

Different fish have different susceptibilities to disease. What is the temp?

 

[smudge_]

a few degrees above standard simply due to the ich.
 
 
And now its just 10 perfectly healthy looking corys and a sick tetra left 

 dont even know what to do about the treatment now.  I can't add more fish without clearing the ich out of the tank, but the corys are the most impacted by the treatment and they seem utterly untroubled by the ich 
 
Im so annoyed by this entire thing, ive had ich before and its never been like this 

 
 
update:

huh spoke to the lfs store I bought the fish in, said id treated it with that interpet white spot treatment I bought in a closer fish shop, they said its utterly useless and they stock every interpet treatment expect that one.    Wonderful

no wonder they didn't get better.