Hot Tub Forum
Original => Hot Tub Forum => Topic started by: In Canada eh on January 28, 2007, 12:19:32 pm
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I know this is a similar thread to the alkalinity topic but I have a couple questions and don't want to hijack the other post. For those of you that remember our water has a constantly rising pH when all levels are balanced. So, I did a little experiment ( Vinny would be proud ) and let the alkalinity fall to where it wants to and just watched the pH. Strangely our pH seems to hold nicely when the alkalinity is down around 60 to 70. Here is my question, what are the possible side effects of low alkalinity and can low alkalinity do any harm to the equipment?
Thanks in advance
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I don't have an answer to your question but thought you might want to know that my ph also stays more stable when my alk is in the low range of "acceptability". (90-100 is best for my water) Once it gets to about 80 though, ph starts to really drop quite fast.
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Why Not
Strange isn't it that your water behave exactly opposite of ours, if I keep the alkalinity up around 100 my pH will climb as the alkalinity will drop and then at some point the pH will fall back into range
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Good Job!!!
Reading the Taylor book it warns about low alkalinity ... but I don't know if I truely believe it.
It says you can have pitted concrete, disolve metals and staining of walls.
But using the Watergram that comes with the Taylor, a reading of 60 with a calicium harness of 150 (low end of hardness scale for spas IMO) and a temp of 104º gives a PH of approx 7.75 (in between 7.7 and 7.8), according to the saturation index if the PH of the spa water is +/- 0.5 of this number then you are theoretically balanced.
Balanced water is NOT supposed to be bad for your pool or spa. Adjust something - PH, Temp, Alkalinity or Calcium and the "balanced" point is somewhere else.
We get crazy at times worrying about minute details and forget that if something is a little off we probably won't suffer unless it goes for a very long time (say PH of below 7.0 or calcium hardness above 500) or a combination of factors to make something happen via chemical reaction (high PH and high calcium causes the calcium to be deposited onto the spa)
My water out of the tap is low in alkalinity, low calcium and a PH about 6.8 ... my copper piper are 35 years old and my cast iron drain pipes are still around. A PH of 6.8 for 2 weeks in a spa may not be a big deal.
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Why Not
Strange isn't it that your water behave exactly opposite of ours, if I keep the alkalinity up around 100 my pH will climb as the alkalinity will drop and then at some point the pH will fall back into range
Definetely..... I'll never understand why everybodies water is soo different. :-/
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Why Not
Strange isn't it that your water behave exactly opposite of ours, if I keep the alkalinity up around 100 my pH will climb as the alkalinity will drop and then at some point the pH will fall back into range
I have said this before, I don't think that any water can be a snapshot as to what to do. Just because you get great results doing a,b,c doesn't mean I will. Which is why some people swear by N2 and others don't.
My tub is holding onto chlorine for days. I can put 3 PPM in and it will be there for almost 6 days dropping very slowly. My PH has stayed steady for about 3 weeks now at 7.4 ... I can't answer why but my water is clean and clear.
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Good Job!!!
Reading the Taylor book it warns about low alkalinity ... but I don't know if I truely believe it.
It says you can have pitted concrete, disolve metals and staining of walls.
But using the Watergram that comes with the Taylor, a reading of 60 with a calicium harness of 150 (low end of hardness scale for spas IMO) and a temp of 104º gives a PH of approx 7.75 (in between 7.7 and 7.8), according to the saturation index if the PH of the spa water is +/- 0.5 of this number then you are theoretically balanced.
Balanced water is NOT supposed to be bad for your pool or spa. Adjust something - PH, Temp, Alkalinity or Calcium and the "balanced" point is somewhere else.
We get crazy at times worrying about minute details and forget that if something is a little off we probably won't suffer unless it goes for a very long time (say PH of below 7.0 or calcium hardness above 500) or a combination of factors to make something happen via chemical reaction (high PH and high calcium causes the calcium to be deposited onto the spa)
My water out of the tap is low in alkalinity, low calcium and a PH about 6.8 ... my copper piper are 35 years old and my cast iron drain pipes are still around. A PH of 6.8 for 2 weeks in a spa may not be a big deal.
Thanks Vinny,
I'm going to stop worring about alkalinity so much as long as my pH stays in range
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In a similar post or 3, i said the same thing. get your pH where you want it and dont worry too much about alk.
Neo
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...For those of you that remember our water has a constantly rising pH when all levels are balanced. Strangely our pH seems to hold nicely when the alkalinity is down around 60 to 70. Here is my question, what are the possible side effects of low alkalinity and can low alkalinity do any harm to the equipment?
Water management guidelines seem to to have been developed from the perspective of neutral water that needs most components to be added, and I suspect that they were developed for pools/commercial applications and extrapolated for residential spas. I've often wondered if TA recommendations are based more on cement/plaster/tile pools and spas that need to prevent minerals from leaching from the walls, than the needs of an acrylic spa where the main benefit is pH buffering.
I agree with Vinny, balance is more important than making sure each component is within the standard range. Starting out at high pH levels seems to require a different approach than what is recommended in water management guides. In my spa I have to get TA down below 120 before I can start making pH move. I find TA 80 to be equilibrium. Above that and pH wants to rise, below it and pH is fragile and susceptible to quick drops when any low pH material like unbuffered MPS is introduced.