Adjusting my pool chemistry

I have an in-ground fiberglass pool. I was away for a week and just tested my water. Right now I have 0 chlorine and a pH of slightly higher than 8 (which may explain why my water is cloudy right now). My pool is about 27,000 gallons.

On hand, I have muriatic acid, shock and chlorine tabs. I just finished vacumming the pool to waste (cleaning up some residual algae from the bottom and sides) and am refilling it.

Can I go ahead and adjust both my pH and my chlorine at the same time? Or, do I do one, and than the other?

I need a quick answer so I can start this process as soon as I am done filling.

Thanks.

Add some muriatic acid first to drop your pH down a little bit. If it were my pool, I would add a quart slowly in front of a return jet, wait a few hours to let it mix. Then, retest pH and add more acid if needed. An hour or so later after you add the last dose of acid, start adding chlorine. The reason I say adjust pH first is because once your raise your chlorine to shock level (which you need to do since you have algae), you won't be able to test pH. High chlorine levels make pH readings inaccurate.

Do you have a CYA reading? What is the ingredient in your shock and in your tabs? Look closely at the tabs to make sure they don't have copper in them.

The test kit we recommend is the Taylor K-2006 or 2006C which you can get through the test kit link in my signature.