The test will be most accurate following procedures exactly and understanding the visual interpretations Taylor published. Still, even your darkened test lets you know that you need a lot of FC just for normal maintainece, even more for shock. Unless someone says different, use 90 as your CYA for now.
We can retest and adjust CYA later. Since PH is 7.2 you're ready for this SLAM. Reread the SLAM page and ask any questions. Get it to CYA 90 shock level and keep it there. Test 2x a day min, first two days 3-4 even better if you can easily.
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Just pour the bleach in the pool really slowly right in front of the return water jet, again really slowly. If pouring the whole jug would take 2 mins i can't imagine that threatening the plaster since you have algae to fight. Wait 30 mins between chemicals is general rule I believe.