Since you state that the water is still greenish, I don't think you have killed all of the algae. One gallon of the 10% liquid chlorine is only going to add about 4ppm of chlorine. I think you need to shock the pool. Take a look at the chart at this link that explains the relationship between CYA and needed chlorine. http://pool9.net/cl-cya/
Go ahead and add 3 of those gallons of 10%. That should add about 12ppm. An hour or so after adding it this evening, test your chlorine and make note of the FC and CC readings. Then, in the morning within an hour of sunrise, test again. We are looking for overnight chlorine loss. If you lose more than 1ppm or have a CC reading greater than 0.5ppm, then you know you are still fighting something in the water and would need to continue to keep your chlorine at shock level. Continue to do so until you can pass the overnight test. Then, keep the chlorine high for one additional day for added insurance. At that point, you can let the chlorine drift down but keep it within the range noted in the chart linked above.
Your CYA is too low. After you get this cleared up, you should work on raising it to around 50ppm.
With pH bouncing around, you would probably be wise to bump your alk up some. Aim for about 80-100ppm. You'll probably need around 10lbs of baking soda but don't add it all at once. Do it in 2-3 lb doses. Then after a few hours, add a little more. You can add it slowly through the skimmer while the pump is running. Also keep adding Borax as needed to keep your pH up. It is fine to add the Borax and baking soda one right after the other.
Keep your pump running 24/7 while you are working to clear this up.
Let us know tomorrow what the results of the overnight test are.
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