black widow tetra

I've just come home from work and have noticed that one of my black widow tetras has got a blister like lump on its mouth. I can't really find anything online to help. I changed their water a couple of days ago so levels are normal. I haven't noticed it before so either it's been there a while...

I just discovered that one of my black widow tetras has some hairy white stuff coming out of its damaged eye. I'm not sure if its fungus or what but it looks very similar to some stuff I've seen growing on my driftwood. I don't really know what it is or what to do any help would be...

Hey, I have followed every guide to effectively fish-less cycle an aquarium I think exists on the interwebs, and am now about a week off from adding my fish (provided all goes to plan).  My current plan is to include into my heavily planted 25 gallon tank: 6 Zebra Danio, 8 Black Widow/Phantom...