Do the last.

Since the algae is sticking to the liner, be sure to brush the pool everyday while fighting the mess. That's a big chunk of your problem. Vacuum everyday to waste--yeah, you lose water, but it's still LOTS cheaper than draining and refilling.

Be sure to keep your FC high--check it 3x a day, morning, when you get home from work, bedtime, and add bleach as needed. Your FC should be at least 15ppm (assuming 30ppm of CYA or more) all the time--aim for it.

Remember Carl's Rule of Thumb: 1 gallon of 5.25% bleach adds 5.25ppm to 10,000 gallons. 1 gallon of 6% adds 6ppm to 10,000 gallons. For 20,000 gallons, you need 2 gallons to get the same raise.

If this gets you confused, download MWSmith2's bleach calculator program and just plug in what you need, and how many gallons your pool is. It's free and it works! (and it won't infect your PC...)