The short answer is yes, go ahead and add some liquid shock but you'll either need more shock soon or go to wally and get about 12 large jugs of bleach. The GValue brand is usually hard to beat in price but you can decide that yourself.
As for more detail:
Lets assume a CYA of 50 for now.
Using the CYA Chart recommended shock level (its a bit more aggressive than pool calculator) your shock level is 20.
This means you have to add enough liquid chlorine to get you to 20ppm. According to pool calculator, to get there the first time you'll need to add 2 gallons 3 quarts or 2.7 (128 oz) jugs of 12.5% assuming your FC is 0, which it likely is. Heck, I'd just pour all three in cuz some of it will immediately get consumed.
Keep the pump running and add it in front of the return jet. If you have a brush you can put on the pole and brush the sides (takes about 10 minutes) and bottom to at least loosen the existing algae. What is going to happen is the liquid chlorine you add is going to rapidly get consumed by the organics at work.
About 30 minutes after you add the chlorine, take a test strip and dip it in the water. See what reading you get. (No its not ideal, but it's something) If you get zero, then add to 20 again. If you get say 5, then put 5 in the current section of the pool calculator and target 20 again. Repeat hourly if possible. Brush when you can. Keep doing this process until you go to bed tonight if you can. When hubs gets home do the sweeping or what not. In between, go about your regular business with the other stuff. If you can get a picture posted it may help so we know what you are dealing with and it will help you see progress.
Basically, you are somewhat doing this blind but at least gaining headway and possibly doing some damage control.
