Help, Low Alk, High PH, low Calcium

[Gomboman]

Sorry for asking these questions.  I'm sure it's been covered before.  My water out of the tap is all over the map.  Alk is 81, PH is off the map high, and my calcium is 88.

I just re-filled the other day and thought the alk was good enough (81) and attempted to lower my PH. I'm using PH/Alk Down (Sodium Bisulfate) provided in my start up kit.  Of course, when I add the PH/Alk down to address my PH, the alkalinity falls below the lower spec. below 80.

Yesterday, I added about 2 oz. of baking soda to get my alkalinity up to about 120 to basically start over.  It didn't raise the PH too much higher than it was.  Next, I again added some PH/Alk Down (Sodium Bisulfate) one once at a time.  When I do this my alkalinity seems to be lowering but my PH is still high 7.8.  If I add any more sodium bisulfate my alkalinity will be too low again.

I'm not sure if all this made sense but is their a product that will lower my PH and not lower my alkalinity?  Also, if I need to raise my alkalinity only again, should I use baking soda or my PH/Alk Up (Sodium Hydrogen Carbonate)? Is this common to start out with PH and alkalinity readings so much out of sync?  

Oh, one last question.  My calcium levels are also low out of the hose 88.  I hear conflicting data whether or not I should worry about this.  I've added some Calcium increaser but it takes a lot and I'm half way to the 150-300 range.  Do I really need to be at 150?

The next time I re-fill I will probably use a different strategy but I'm not sure what that will be?  

[Tman122]

7.8 sound ok to me on your PH, instead of trying to get it micro managed just leave it there and see where it goes. Make all your adjustments slowly over time. Never force feed water balance to your spa, feed it slowly over time (a couple weeks if need be) Or it will puke on ya.

[keating]

if you need to get your alk up, add baking soda or an alk up product.........then once your alk is ok, I've heard you can add muriatic acid to get your pH down without lowering your TA.

as for your hardness, I'd be all over getting that up....personally.....it may not be too much trouble to the spa itself, I'm not sure, but it'll be tough on your concrete pad, assuming you have one. water that is slow in calcium will leach calcium from anything it sits in contact with.....just get it to 150 and call it a day.
low calcium and low alk are gonna make your pH swing all over the place, as they are pH buffers.

I have the opposite problem......takes about 4 oz of best defense (stain & scale type product) to get hardness below about 400, then about 26 oz of ph down to get alk and pH into a reasonable range.

[Ehizzle]

Wow keating 26 oz. of ph decreaser. Either you have off the charts ph or you have a 2000 gallon spa.

[Soakin]

Wow keating 26 oz. of ph decreaser. Either you have off the charts ph or you have a 2000 gallon spa.

I use about the same amount in my 525 gallon spa.  My city water tests perfect (other than high hardness)out of the tap, but goes up to off the chart values for pH and TA a day or two after a fill.

[Gomboman]

Thanks Keating,

I didn't know that calcium acted as a PH buffer.  I thougt it was only alkalinity.  

I took the below section from  Northman's FAQ on Doc's site.  Even though he doesn't think you need to be in the 150-300 range, I will probably attempt to anyway for insurance.

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Northman FAQ
Calcium Hardness In Spas

Calcium Hardness for water is controversial. Some dealers say you need it others say you don't. Based on water chemistry recommendations, you need a calcium level of 150ppm - 300ppm. Soft water is aggressive and will cause pitting and etching of concrete, grout or plastered surfaces as it seeks to dissolve calcium into the water from whatever contact source.

However calcium's purpose (in my opinion) is not to prevent the water from being corrosive (as that is what the pH is for), but rather to add a temporary level of protection to the surfaces that come into contact with corrosive water, particularly heaters, metal fittings and concrete pool surfaces. The way calcium does this is by leaving a thin calcium film on these surfaces, when the water balance of pH, alkalinity and calcium is ideal. If your pH does drop below 7 (ideal is 7.4-7.6) the corrosive water has to first etch the calcium film off before it can corrode the metal or concrete surfaces adding a degree of temporary protection to these vulnerable surfaces.

It should be noted that if the water balance is not right, for example the pH is to high, and then calcium can cause excessive scaling. This scaly build up starts in the heater and in extreme condition leaves a chalky residue or scale at the water level and in the filters as well as causing cloudy water. When this scale builds up excessively on the heater or in the heat exchangers, then the calcium acts as an insulator causing the heater to be inefficient or even worse overheat and burn out on an electric heater, or cause a heat exchanger meltdown on a gas heater. There are chemicals that prevent or reduce scaling when your pH goes up or your calcium levels are to high, but at the same time it reduces the beneficial effects of the calcium hardness in addition many brands of water softeners promote foaming with extended use, making you wonder why you put calcium in, in the first place.

If you do have a concrete pool or spa then I recommend the careful use of calcium and remember complete water balance is essential.

However I have found no benefit to using calcium hardness in modern spas. If you adjust your alkalinity to 100-130ppm and keep your pH as close to 7.5 as possible, the spa water is not corrosive with out calcium, and will do no damage to your equipment. If you do decide calcium is right for you, be aware that if your pH is low corrosion can and still will occur.

Also keep in mind when using calcium that a high pH can do plenty of damage as well, (such as clogged filters, heater damage, scale buildup in plumbing or jets) where as without calcium a temporary high pH is much less detrimental and causes no long term damaging effects.

When conditioning your water it is always best to adjust alkalinity first, calcium hardness second and finally the pH as the pH is affected by the amounts of calcium and alkalinity in the water. If anyone can give me a good argument as to the need for calcium, I would love to hear it.

if you need to get your alk up, add baking soda or an alk up product.........then once your alk is ok, I've heard you can add muriatic acid to get your pH down without lowering your TA.

as for your hardness, I'd be all over getting that up....personally.....it may not be too much trouble to the spa itself, I'm not sure, but it'll be tough on your concrete pad, assuming you have one. water that is slow in calcium will leach calcium from anything it sits in contact with.....just get it to 150 and call it a day.
low calcium and low alk are gonna make your pH swing all over the place, as they are pH buffers.

I have the opposite problem......takes about 4 oz of best defense (stain & scale type product) to get hardness below about 400, then about 26 oz of ph down to get alk and pH into a reasonable range.

[keating]

Wow keating 26 oz. of ph decreaser. Either you have off the charts ph or you have a 2000 gallon spa.

Yeah.....off the charts pH...hard, alkaline well water.
First fill needed most of a 1kg bottle of "adjust down" to get in the proper range, then small doses an ounce at a time to keep it there over a two week period.

refilled last night, and added about 26 oz over a few hours with both pumps and the blower running on high, then sealed it up for the night....dipped a test strip this morning, and ph is pretty much perfect...7.6, and TA reads as the lower of the two colour blocks in the "ok" range...can't remember the number.

The guy I bought the house from had a hot tub as well.....he said on a new fill, he used to pour 2.5 cups of muriatic acid (from the pool store) into his spa to get down to 7.4-7.6 range.

[Brewman]

Our tap water is way high in alkalinity too, and i use at least 24 ounces of Ph decrease to get it back into range whenever I put in new water.
 I go thru a lot of this stuff in a years time.

[keating]

Brewman, check some pools shops rather than the spa "only" dealers....I bought 3kg of ph down product from a local catalina spa dealer, who happens to sell/service pools as well as spas...cost $12 for 3kg....less glam packaging than the spa targetted product, but same chem in same concentration..... vs $7/kg for the Arctic Pure "Adjust Down" product.
They also had 10kg buckets, but I figured at 26oz per fill, plus maintainance doses, 3kg should get me through a year or so.

[Brewman]

I get my Ph up and down from the local fleet farm store.
I pay about the same for a huge container (many pounds, can't remember for sure- possibly 6) as I was paying at the spa dealer for a skinny bottle.  And the ingredients are the same.  I get my alk increaser at the grocery store.