Sequence For Raising Ph And Ch After Refill

[BlueSpa]

I'm about to do a refill on our spa and have had great luck with the 50ppm Borates helping to stabilize the pH. Because our well water has a low pH I was going to use a little Borax to raise the pH to about 7.6, then finish with Boric Acid (or Gentle Spa) to get to 50ppm Borates without having to add acid.

Thought I'd do a little reading on what to expect with the Borax and I read Richard's comment about creating calcium precipitates - "Calcium should not be added within 12 hours of any pH or alkalinity raising product."

I've never created any precipitates in the past and usually waited an hour or so between additions of the Sodium Bicarb alternately with Calcium Carbonate, but maybe I've just been lucky . . .

Since our water has virtually no Calcium, I'm wondering if it's OK to wait till the next day to start adding the Calcium Carbonate??

(Our spa is 650 gallons if that makes a difference.)

Thanks!!

[waterbear]

I'm about to do a refill on our spa and have had great luck with the 50ppm Borates helping to stabilize the pH. Because our well water has a low pH I was going to use a little Borax to raise the pH to about 7.6, then finish with Boric Acid (or Gentle Spa) to get to 50ppm Borates without having to add acid.

Thought I'd do a little reading on what to expect with the Borax and I read Richard's comment about creating calcium precipitates - "Calcium should not be added within 12 hours of any pH or alkalinity raising product."

I've never created any precipitates in the past and usually waited an hour or so between additions of the Sodium Bicarb alternately with Calcium Carbonate, but maybe I've just been lucky . . .

Since our water has virtually no Calcium, I'm wondering if it's OK to wait till the next day to start adding the Calcium Carbonate??

(Our spa is 650 gallons if that makes a difference.)

Thanks!!

How low is the CH in your fill water? You only need a CH of around 125 and not higher. My suggeston is to add the calcium first while the pH is low and then the next day add your borax and acid (gentle spa is just borax and dry acid--you can just use borax and acid yourself and save a lot of money.)

Also, what is the TA of your fill water? You want it around 60-80 ppm before you add the borates so that might need adjustment first.

Adjust one thing at a time, don't try and adjust multiple water parameters at once and give 24 hours in between for readings to stabilize.

[quantumchromodynamics]

A few notes:

1) Calcium increaser is Calcium chloride, not calcium carbonate.

2) The quote "Calcium should not be added within 12 hours of any pH or alkalinity raising product." was from me, not Richard.

3) Sodium carbonate is much more likely to cause a precipitation reaction than sodium bicarbonate. Even so, you still want to be careful when adding different products. Allowing plenty of time between additions helps reduce the likelihood of having an adverse reaction.

4) Calcium saturation is primarily needed for plaster or grout. Plastic hot tubs do not need saturation and should be kept slightly negative on the CSI. Be careful not to add too much calcium.

[BlueSpa]

I'm about to do a refill on our spa and have had great luck with the 50ppm Borates helping to stabilize the pH. Because our well water has a low pH I was going to use a little Borax to raise the pH to about 7.6, then finish with Boric Acid (or Gentle Spa) to get to 50ppm Borates without having to add acid.

Thought I'd do a little reading on what to expect with the Borax and I read Richard's comment about creating calcium precipitates - "Calcium should not be added within 12 hours of any pH or alkalinity raising product."

I've never created any precipitates in the past and usually waited an hour or so between additions of the Sodium Bicarb alternately with Calcium Carbonate, but maybe I've just been lucky . . .

Since our water has virtually no Calcium, I'm wondering if it's OK to wait till the next day to start adding the Calcium Carbonate??

(Our spa is 650 gallons if that makes a difference.)

Thanks!!

How low is the CH in your fill water? You only need a CH of around 125 and not higher. My suggeston is to add the calcium first while the pH is low and then the next day add your borax and acid (gentle spa is just borax and dry acid--you can just use borax and acid yourself and save a lot of money.)

Also, what is the TA of your fill water? You want it around 60-80 ppm before you add the borates so that might need adjustment first.

Adjust one thing at a time, don't try and adjust multiple water parameters at once and give 24 hours in between for readings to stabilize.

Thanks Waterbear! In the past when I've tested our fill water before any treatment the CH is basically 0 and TA is 10.

[BlueSpa]

A few notes:

1) Calcium increaser is Calcium chloride, not calcium carbonate.

2) The quote "Calcium should not be added within 12 hours of any pH or alkalinity raising product." was from me, not Richard.

3) Sodium carbonate is much more likely to cause a precipitation reaction than sodium bicarbonate. Even so, you still want to be careful when adding different products. Allowing plenty of time between additions helps reduce the likelihood of having an adverse reaction.

4) Calcium saturation is primarily needed for plaster or grout. Plastic hot tubs do not need saturation and should be kept slightly negative on the CSI. Be careful not to add too much calcium.

Ops on 1&2 - another senior moment <G>, good I checked in with the forum, haven't been thinking chemistry for a while!

I usually try to keep the SI between -2 or -1 but didn't know what effect a low pH / lack of Calcium would have on the spa hardware for the short time if I wait to adjust.

Thanks for the help!! Time to pull out the Taylor kit and try to fire up my chemistry neurons.