Ok, if I understand, your CYA is around 80, and your chlorine is 20? If that's true then the pH test is invalid unless you diluted (50/50) the pool water with DISTILLED water. Chlorine levels above 5ppm (or 10 with the Taylor kit) cause invalid results. If you have cloudy water and the Intex cartridge filter, you need to run the pump 24/7 and you still may be a week or two from clear water. [EDIT] The manual recommendations are for "IDEAL" conditions, and that is not where it seems you are. [END EDIT] I'd turn the SWCG off and use bleach to chlorinate TO SHOCK LEVEL (20 to 25ppm for you) until these 3 things are true,
1. There is less than 1ppm FREE chlorine loss over night
2. There is less than .5ppm COMBINED chlorine at sunrise
3. There is no sign of live algae
Doing this will help extend the life of the SWCG, and needs to be done if the SWCG is on or off. It is lots easier to tell what's going on without the SWCG because it adds an indefinite amount of chlorine.

With your CYA level, you're looking at a MINIMUM free chlorine level of 8ppm. Maybe shoot for starting with 12ppm and see if that is still 8 at sundown.

That being said, IF there is no sign of LIVE algae, and you can see the bottom of the pool, and your chlorine level is between 8 and 16, it is safe to swim. Wear old suits. Stirring up the water will help get the dead algae to the filter. Be sure to read
http://pool9.net/cartridge-clean/

ALSO, I'm pretty sure that all Intex SWCGs have a copper ionizer. Copper kills algae fairly well, bacteria - not so much. Copper can stain pools and turn light hair green (it's not chlorine that does that). If you keep enough chlorine to kill the bacteria, that's usually enough to kill algae. You might want to see if you can SAFELY disconnect the copper ionizer.

Good luck!

Pappy