Reducing calcium hardness

[bizbad]

My pool company acid washed the sides of the pool and then dumped in sodium bicarbonite to bring the ph down. I just checked my pool and ta is 250 and ch is over 600 how much water do you suppose I have to drain out of a 14000 gallon pool to bring them back down?

[CarlD]

The questions are not related.

You could dump ALL your water, refill, and STILL have a T/A of 180 (my town's water has that). Or you could have a T/A of 0.

But the calcium can only be removed by dilution. If your CH reading is 600ppm and you want it to be 300ppm (a good number for your pool) you will need to dump half your water.

But to get your T/A down you need to go the stickied thread on lowering T/A.

BTW, with those numbers, your water may well go cloudy soon--as in white clouds. That's not great but it's a WHOLE lot better than an algae bloom. At least it's safe to swim in. Muriatic Acid may clear it up, and getting your T/A down should too.

So replace half your water and re-test. If your T/A is STILL too high (and, remember, you must be testing T/A when pH is in the 7.3-7.8 range or it won't be accurate), then follow the T/A lowering directions.

[bizbad]

The alkalinity here is low so it will bring everything in line.

[mas985]

I would test your fill water for calcium before deciding on replacement ratios. We have well water which can be very hard (read calcium) depending on time of year (we also get surface water) so even if I replace all of the water, my CH can be close to 400.

[Sweet]

If you do have Calcium in your fill water the BleachCalc program can help you determine how to achieve the correct dilution (See the Sticky: Using the Bleach Calculator (http://www.poolforum.com/pf2/showthread.php?t=4735)). You find it under the "More Calc" menu within the BleachCalc program.

[giroup01]

Theoretically though would it possible to increase the pH to around 9.5-10, vacuum out the precipitated calcium, and restore the pH to normal?

[waterbear]

Theoretically though would it possible to increase the pH to around 9.5-10, vacuum out the precipitated calcium, and restore the pH to normal?
Theoretically yes but in actual practice you might find much of it comes out of solution as stain and scale deposits on the pool surfaces as opposed to a precipitate in the water.

[JerryZ]

Theoretically though would it possible to increase the pH to around 9.5-10, vacuum out the precipitated calcium, and restore the pH to normal?

If you have a SWG, and a return that comes off of it, ( pressure side cleaner, for example), you can put a fine mesh (pantyhose) on it and catch the calcium flakes.

[bizbad]

The calcium in my fill water is 50 and ta 80 ph 7.7. Have already started the drain and fill. Working just fine