I have been using the Tundra brand bleach sold at Aldi for my sanitizer this season. It is the 6% type. I was curious to know if anyone else that was using this brand noticed any issues with p.h. rise when using this product. I have had to bring my pool down from the 7.8- 8.0 range about three times this season. I am aware that there are other variables involved in p.h. rise, but aeration and the others do not seen to be an issue.The p.h level of my fill water is very high, so I know that contributes to the issue.I really do not keep track of how much water is replenished in the pool, as I have two sons who like to have cannonball contests with their friends,which also contributes to the rise. Just trying to get my hands around all variables involved to better control the health of my pool. Thanks
ALDI BLEACH CAUSING P.H.RISE?
- Thread starter tnewton7
- Start date
pH will rise om it's own because of outgassing of CO2 when using unstabilized chlorine sources. It's normal. IF you had previously used trichlor for chlorination the acidic nature of it took care of any pH rise and you might have had the opposite prolem of needing to raise the pH and TA as they dropped from continued trichlor use.i
The addition of bleach into your pool results (given a little time) in virtually no change to the pH.
I'd charge them .50 cents per cannonball,,,,that should hold it down (assuming you can ever collect)
I'd charge them .50 cents per cannonball,,,,that should hold it down (assuming you can ever collect)
Good idea Dave on the cannonball charges!! I doubt if I would ever collect on it though. I had read somewhere on here about lye possibly being one of the inert chemicals used in bleach. The e.p.a. does not require the inert ingredients to be listed on the manufacturers site, so it is impossible to tell what these are. I was a past trichlor user so i am sure this is why it was never a concern.
Lye is used in the manufacture of bleach and there is some sodium hydroxide (lye) present in bleach and liquid chlorine (if there wasn't the chlorine would not stay in the solution!) so when you first put it in the pool it causes a pH rise. However, when the chlorine sanitizes and is converted into chloride ions and oxygen it is an acidic reaction to the net effect of adding bleach is pH neutral!
Trichlor, on the other hand is extremely acidic when dissolved in water and still has the acidic reaction when it sanitizes so, in effect, you are constantly adding acid when you use trichlor so you have to replenish the TA and increase the pH on a regular basis. Total chemical usage is much higher with trichlor than with bleach or other unstabilized chlorine sources (assuming that you are keeping your water balanced This is often not the case with inexperienced trichlor users. I have seen too many pools on trichlor where the pH has crashed and TA is nonexistant because of this!)
Trichlor, on the other hand is extremely acidic when dissolved in water and still has the acidic reaction when it sanitizes so, in effect, you are constantly adding acid when you use trichlor so you have to replenish the TA and increase the pH on a regular basis. Total chemical usage is much higher with trichlor than with bleach or other unstabilized chlorine sources (assuming that you are keeping your water balanced This is often not the case with inexperienced trichlor users. I have seen too many pools on trichlor where the pH has crashed and TA is nonexistant because of this!)
I have been using the ALDI bleach since I mentioned it months ago. Probably 120+ containers of it in my conversion from Baquacil. My PH remained at 7.6-7.8 the whole time. I have switched to the 12.5% because the price was cheaper if you figured out the comparitive amount of 6% to 12.5% strength.
The amount of "excess lye" in bleach varies, but even in the most extreme case I've seen with bleach that has a pH of 12.6 (about 0.25% excess lye), this would increase the pH by about 0.2 per month if adding chlorine at a rate of 2 ppm FC per day. 6% Clorox Regular bleach with a pH of 11.4 (about 0.02% excess lye) has an immeasurable increase in pH. 12.5% Chlorinating liquid typically has a pH of 12.5 (a little less than 0.25% excess lye) and would increase the pH by about 0.1 per month at a 2 ppm FC per day rate. I'm talking about long-term after consumption of chlorine -- obviously when bleach or chlorinating liquid (or Cal-Hypo, for that matter) is added to the water, the pH rises but then it drops back down when the chlorine gets used up.
The MSDS for Tundra Ultra Bleach and related sodium hypochlorite products from Vertex Chemical is shown here where it appears that 6% bleach has around 0.2% excess lye and a pH of 12.31. So I would expect it to contribute a little less than a 0.2 pH increase per month if chlorine usage were 2 ppm FC per day.
In addition to the above, the pH rises due to carbon dioxide outgassing as waterbear wrote. This effect is usually higher than the above "excess lye" effect (unless a pool cover is used) and can be lessened by lowering the TA level, by reducing aeration sources, and by having a higher pH target.
Richard
The MSDS for Tundra Ultra Bleach and related sodium hypochlorite products from Vertex Chemical is shown here where it appears that 6% bleach has around 0.2% excess lye and a pH of 12.31. So I would expect it to contribute a little less than a 0.2 pH increase per month if chlorine usage were 2 ppm FC per day.
In addition to the above, the pH rises due to carbon dioxide outgassing as waterbear wrote. This effect is usually higher than the above "excess lye" effect (unless a pool cover is used) and can be lessened by lowering the TA level, by reducing aeration sources, and by having a higher pH target.
Richard
I use Aldi bleach too and have had no problems with the PH rising. My girls love to put the noodle by the return and let the water shoot up in the air. This doesn't cause too much PH rise either.