The water should be light to light medium pink. I would start with light pink first. See how the fish are reacting to treatment, then add a bit more, drop by drop by drop until its a medium light pink. That's why the video is the best help. The treatment if 4 hours. Check on the fish every 15 minutes to see that the water is still pink. Have Prime or hydrogen peroxide handy just in case you OD on the PP, and need to neutralize. After 4 hours, do a 50% water change with prime. Use aged water if you can as it is less stressful on fish.
This is the best treatment for surface infections - fungus, columnaris. It's also a great treatment for anchor worm, ich, and even flukes.
Keep the fish in QT for a few days. Add some salt at 1tbs./5 gallons if your fish can handle salt (no scaleless fish like plecos). The salt will encourage the development of the slime coat.
You can retreat PP in two days if the infection is still there.
Before placing the fish into the main tank, do a major overhaul - 50% water change, gravel vac, wipe down walls of tank. Replace filter floss, rinse out media in tank water. Wipe down filter walls and tubes. Keep changing the water in the main tank every day at least 25% for a week to ensure that the water is pristine.