Wow...this is a job for the experts

[chem geek]

But what does the all red alk test mean?????

I believe the Total Alkalinity test from Taylor (and others) uses a combination of "bromocresol green" and "methyl red" pH indicators that turn from green to red at around a pH of 4.5 so the fact that the TA test starts out red means that the pH is already below 4.5

I would expect that the water is not only low in pH, but probably has much of the carbonate buffer removed from it as well (the acid from the TriChlor tabs will lower pH and the TA while the carbon dioxide will outgas quickly so I suspect the TA is also quite low). Therefore, I recommend adding Soda Ash, aka [EDIT] Washing Soda [END-EDIT] (not Baking Soda) aka Sodium Carbonate (typical "pH Up" in pool stores) since that will raise both your TA and your pH. If you follow Carl's advice and add Borax, then you'll likely also need to add Baking Soda, aka Sodium Bicarbonate.

If your TA is really very low, then adding relatively small amounts of Borax by itself will cause fairly large swings in pH. Add some, wait to circulate (an hour should be OK if the pump is running) retest pH and add more if needed, etc. If you add either the Sodium Carbonate or Sodium Bicarbonate, then you won't get as large a pH swing.

Richard

[CarlD]

Chem_geek is not wrong, of course. Your T/A is probably 'way too low. But my recommendation for Borax is to get pH into the normal range so you can see what else is going on. Baking Soda's cheap, so is Borax.

But if you do go the soda ash route, Arm&Hammer WASHING Soda is the right stuff (Sodium Carbonate) and even cheaper (in my supermarket) than Borax per pound. The Washing Soda box is Yellow, not orange. It will be in the laundry products section.

Either way should be fine, but you MUST get pH up.

[Poconos]

If I was ever in a situation where the chems are as messed up as they seem I think I'd try rweaking things on a small scale first, just to see if whatever you do yields the expected results. a.k.a the biggest plastic trash can you can find and scale the chemical additions accordingly. Any damage that can be done is probably already done so the additional time it takes messing with a trashcan full of pool water won't matter. Can also save a bunch of $$$.
Al

[bluecamel]

Actually 4 boxes in, but when I measured after 3 there had been no measurable change. Alk test still red from the get go and ph test still holding on sunshine yellow. We will add more the rest of the day.

I am surprised since the alk is so low, I thought the ph would swing up more quickly. I will update agin after 6 boxes.

Is there a point at which I get no change that I should start doing something else (6 boxes, 7 boxes maybe??????)?

[chem geek]

I am surprised since the alk is so low, I thought the ph would swing up more quickly.

If the pH were 4.0, then it would take about 5 boxes of Borax to raise the pH to 7.0 and almost 7 boxes to get to 7.5

If the pH were 3.0, then it would take about 11 boxes of Borax to raise the pH to 7.0 and 13 boxes to raise the pH to 7.5

So it would seem that you need to keep going. If you use Borax, then you will end up with high levels of borates in the pool. Each box of Borax adds about 3.6 ppm Boron (Borates) to the pool. So a positive side effect of raising the pH in this pool is that it will be close to having the algicidal properties of the pool that is talked about in this thread.

Richard

[CarlD]

Please beware that a pH maintained at 3 in a vinyl pool may well have already ruined the liner.

Sorry to be the bearer of depressing news....

[bluecamel]

Thanks for the great link on the borate experiment. We are moving the ph, but not as much as I had hoped. (30 drops of base demand now puts me at 7.2).

Once I get the ph in measurable range, is the next step TA? And should I keep it around 80 like the borate experiment? Also, I will retest the CYA, but I am sure it will be over 100. If so, I need to use the CYA/alkilinity equation, right?

Advice appreciated because I do not want to over do one thing trying to correct the other.

They know that their liner is probably toast. I actually think it was pretty dead when they moved in. The previous owners have been running a very clear/high chlorine acid bath for some time. They never used the pool so they only cared if it was clear.