Total Alkalinity=0, yes zero!

[waterbear]

TA is a measure of the bicarbonae in the water. When the pH is very low there will be no bicarbonate, it will all be in the form of carbonic acid (CO2 dissolved in water) so what you are seeing is to be expected when the pH is very low and is common when a pool is run on trichlor tabs, which are very acidic (and TA is not monitored weekly).
You want to get the pH up as quickly as possible since very low pH (which this pool certainly has) can damage equipment and vinyl liners. Baking soda is not going to be that effective at raising the pH if it is very low. Get the borax! If your Taylor kit has a base demand test (if you have the K-2005 or K-2006 it will) use that but add twice the amount of borax for the amount of soda ash it says to add. If the demand test is out of range (which it very possibly is) add two boxes slowly through the skimmer and retest after about an hour of circulation. Keep that up until you get a pH reading above 7.0 or until the base demand test brings the pH up above 7.0 in 10 drops or less and consult the treatment table in the booklet that came with your Taylor kit to determine how much soda ash to add and then add twice the amount of borax.

[myLABSpool]

Thanks Waterbear and The Goose. We will focus on the pH rather than TA for my neighbors pool at this point.

My Taylor kit actually has the base demand and acid demand test, I've just never used them because I've never had that problem. Waterbear thanks for mentioning that.

So it took 30 drops to bring the sample to the pH range of 7.4-7.6, so based on what the book says, it says to add about 18-20lbs. Based on what you said to add 2x that amount of borax--- so I've instructed him to add 38 lbs of borax into his 24K gal pool.

Thanks ---will provide updates later.

Waterbear you are correct about the trichlor tablets. He uses them all the time and I told him to stop using them because of the acidity and CYA---his CYA is 80, so I said use no more for the rest of the season. I told him stick with straight liquid CL.

[Watermom]

Do NOT have him add 18-20 lbs. of Borax all at once!

[myLABSpool]

Thanks to all that helped on this thread. I got my neighbors pool in order. It took about 40 lbs of borax in 24K gal of water in his vinyl IG pool to get the pH up to about 7.4. The TA is still around 50, so I'm going to have him add more baking soda to get that right.

[Watermom]

You are welcome! Now, it is time to go swimming!