From the first photo the Ich doesn't look very bad yet. Get ALL the fish out of the main tank and into QT. The QT can be BRUTE totes or something similar. Fish do not require much in the way of lighting. They will need pristine water conditions while you administer the hypo treatment.
The link that Kurt gave is the best hypo treatment explanation around. You want to take about a week to lower the SG
to 1.009, keep it there for a month, then take a week to SLOWLY raise it up to 1.025 or whatever your main tank is at.
Be prepared for daily 10% - 20% partial water changes for the first couple of weeks to maintain water quality. You also need some type of filtration. A hang on with a biowheel or corner filter works fine for this. PWCs will keep the water pristine while the biological filter is coming online. I leave a biowheel in my sump for use in the QT when needed.
A couple of years ago I had to remove all the rock from my 125 to get all the fish out. It was worth it in the end.
I just got a blue tang 2 weeks ago. It's still in QT and growing, though I have noticed a bit of flashing the last couple of days. Not spots yet, but it will remain in QT until I'm sure.
Good luck with the treatment. Hypo is the way to go.