how to lower if I need to? alkalinity of 170

[mas985]

Timmie,

First alkalinity of 170 is a bit high for pool water but my house is over 240 so it is safe to swim in.

Next, in your original post, you asked how to reduce alkalinity which is why I gave the link I did. Did you not understand the procedure or were you looking for something else?

[CarlD]

I have to disagree. For an ordinary vinyl pool, a T/A of 170 is nothing to worry about and nothing to lower. Not until you hit 200 do you have a problem, so I like to limit the safe range to 180.

Don't bother lowering it. Don't be afraid to swim in T/A of 170.

[mas985]

Sorry Carl, I guess I assumed too much. Although he did not say he had a heater, according to Ben:


What should my TA be?
Somewhere between 50 and 200 ppm. If you've got a heater, it usually should be lower than 150 ppm. If you've got a plaster or concrete based pool, it usually should be higher than 80 ppm.


Because I have a plaster pool and high calcium, I like to keep mine between 80-120.

[timmie]

Hi, the "he" is actually a "she". Just to clarify, my heater doesnt work so I dont think it has anything to do with that. I also did not understand the link that I was sent here to look it. Its too technical for me? Is it the rainwater that raises the alkaline??

[medvampire]

Timmie
There can be several causes of a high ALK. I have you tested your fill water ???
Put simply ALK is the restance to ph change present in a body of water. The higher the ALK the harder for change to occur. The restance to ph change is a good thing but like fatty foods too much is bad. High ALK can cause mineral deposits to build like the cholesterol from the fries I had for lunch plugging my arties are like the deposits that may form in your pool heater or on other surfaces. As for taking a swim it shouldn’t hurt you my pool is around 190 right now. To get a great answer the pros here they need more info. You might also want a good test kit. Ben kits are the best from what I have seen.
http://www.poolsolutions.com/cart/shopping.php

Pool size – Given
Free Chlorine
Total Chlorine
PH
ALH
CYA
Total or calcium hardness
Pool surface
Heater and type

Later
Steve

[CarlD]

While Steve is right in explaining what T/A does, the levels that are recommended here are pretty simple:

If you have a gunite/concrete/tile pool: 80-125ppm
If you have a heater or SWG, generally the same, but the metal composition of both can affect the numbers. Still, 80-125 is safe.
HOWEVER, if you have a vinyl pool, without a heater or SWG, you can safely go as high as 180ppm without worry. That's a ballpark number of course. You are pushing your luck at 200ppm, especially if that reading is taken at a lower pH.

While T/A is a "stabilizer" for pH, it DOES go up and down as pH moves. T/A doesn't prevent pH movement, it just makes it harder to happen. It keeps pH from pogo-ing up and down.

So if you are at the suggested upper limit with a pH of, say, 7.1, then, if your pH rises to, say 7.8, your T/A will probably go well over the max, opening the potential for problems.

This is why 100ppm is such a good target--there's lee-way either way. For a vinyl pool, you have a far vaster range.

I repeat: a reading of 170ppm in a vinyl pool without a heater or SWG is FINE and can be left as is with no impact.

[river-wear]

Okay, I found this thread trying to find an answer for my situation and still feel a little lost. Please help. I have Ben's kit and got the following results:

FC- 3
CC- 0.5
pH- 7.5
Alk- 190
Cal- 140
Cya- 35-40 (I'd guess 37)

I have a heater and a SWG so I'm worried about the high Alkalinity. I just filled the pool about 2 weeks ago after a major remodel. It's concrete with a fiberglass lining. My Autopilot manual says the TA should not exceed 150.

I saw the other posting referring to a procedure to be followed carefully, but haven't found that procedure just yet.