preeble,
It's difficult to balance a new pool using dry acid. Liquid acid goes into solution quickly and will give you quicker response. Make sure you use a good quality test kit with new reagents.
Make sure you are looking at the PH side of the kit. Darker red means add more acid and orange/yellow means too much. I know these last two sentences may seem dumb, but I've had customers confuse acid demand and sometimes confuse the PH and chlorine sides. Good luck.

Thanks - so you are suggesting that I just put in muriatic acid? Assuming that my pH is ~8 in a 24k gallon pool, about a gallon at a time is appropriate?

Just 19.2 oz. of muriatic acid should drop pH in your size pool by .2, say from 8.0 to 7.8. (If you wanted to drop your pH by .4, say from 8.0 to 7.6, you could add 38.4 oz.) So....a gallon would be way too much, if your pH is truly 8. A gallon could drop your pH well below 7, which you don't want to do.

Double check that your chlorine level is appropriate...sometimes very high chlorine levels will give you inaccurate (seemingly too high) pH readings.

Thanks! I will use about 1/3 of a gallon for now and see what happens. My chlorine level is virtually 0 at this point. Have shocked it once already and will do so again a few hours after I add this acid. At this point, I just have some tri-chlor tablets floating in a duckie.

When you add liquid Muriatic acid, If you want to drop the pH you should distribute the acid in the pool. If you want to drop the Alkalinity you pour the acid in a steady stream into one spot in the deep end. Liquid acid works much better for balancing with a new pool or resurfaced pool as mentioned above. You are best to adjust your pH first and then do your shock. You shouldn't add acid and chlorine at the same time. I just had my 25 year old pool resurfaced. I typically added chlorine at night so it would work through the night. Sunlight dissipates unstabilized chlorine so on a hot day it can disappear in a few hours. If you are adding acid to adjust your pH, you should be running your pump when you do this to mix the water. You don't need to panic on this. A new pool will take 30-60 days of steady chemical additions. Once you are out past 30 days it will get easier. Just keep on it each day with your testing, chemical additions and brushing down the sides and bottom.

..Doyle

It's better to adjust your pH with numerous small doses than one large one. Add a little, test again in a few hours, repeat.