My Neons and Plecos got ich. Zebras showed no white spots. Cleared it up with copper sulfate (although I suggest salt + heat if you want to house snails in that tank). Got through it with no deaths.
Now I'm dealing with Columnaris, which only seems to be affecting my neons (which is why I initially thought it was Neon Tetra Disease). It's day 3 of treatment and I think it working. (One of my neons is hiding, and I think its the most heavily affected one, so I can't tell for sure).
Conclusions:
1. Watch your neons, if there is something in your tank, they will probably get it first.
2. Zebras are the Supermen of the fish world. Never seem to get sick.