The Great Tetraborate Experiment!

[waterbear]

I have been toying with the idea of adding borax to 50 ppm to see exactly what effect, if any, it would have on stabilizing pH. My borate test strips arrived last night so today I tested my water:
FC 5 ppm
CC 0 ppm
pH 7.6
TA 120 ppm (before stabilizer correction)
TA 97 ppm (after stabilizer correction)
CH 220 ppm
CYA 70 ppm
Salt 3500 ppm (used the readout on my Aqualogic which is usually about 100 ppm high so I am estimating about 3400 ppm which is where I was last Friday when I tested it)
Borates 15 ppm (measured with AquaCheck borate test strip. I have used Borax in the past to raise pH)

Today I added 1 box (4 lbs, 12 oz.) 20 mule team and 1 pt muriatic acid to offest the pH rise. (might have to add more acid. I am being conservative, based on the recommendations for Proteam Supreme)
I will test the water in a few hours for pH, TA, and borates.
According to Bleachcalc this amount of borax should raise my pool to 50 ppm but the dosing chart for Proteam Supreme requires a lot more, and the pentahydrate uses less by weight than the decahydrate (20 mule team).

I have been conversing with chem geek (Richard) about the dosing and these discrepancies. The aquacheck test strips are designed for testing Proteam Supreme. We shall see what the outcome is.

My main purpose in this experiment is to see if I get less pH rise with my SWG by adding the tetraborates. (or a slower pH rise). Currently it takes a little over 2 weeks for my pH to hit 7.6 from 7.2. I add 1 1/2 pts. acid every three weeks which lowers me back down to 7.2. I want to see if the borates will hep keep the pH more stable as claimed. Many of the SWG monthly mixes contain tetraborates supposedly for this reason along with boric acid to offset the high ph...adding muriactic acid will form boric acid in the water so this just eliminates that step. I know NaturalChemisty's Salt Water Magic contains the tetraborates and I will bet that Mineral Springs by Bioguard does also.

I will post my results in this thread as they become available. This might turn out to be useful info or a bunch of junk....don't really know yet.

[Rangeball]

I have never used borax and have a constantly creeping PH. Will be very interesting to follow along.

[waterbear]

Just checked my water and borates hadn't moved...still reading 15 ppm. If the proteam dosing chart is the correct one then I only added about another 6 ppm which won't show up on the test strips.
pH was off the scale. Added another quart of acid....in line with Proteam recommendations (and my acid demand test in my Taylor kit) so I will wait a while and retest. Gotta buy some more borax also.
So far this looks like what Richard and I expected and might point to a dosing error in BleachCalc.

[waterbear]

ok, tested borates and pH.....borates still reading 15 ppm and pH is at 7.6.....so 1 box of borax takes about 1 1/2 qts (48 oz) acid to neutalize the high pH. This is exactly in line with the Proteam dosing which says 10 oz. acid per pound. I put in 4.75 lbs (contents of one box) and it took 48 oz acid to bring the pH back to 7.6.

After I took the readings above I added 2 more boxes and a half gallon of acid. This was about 45 minutes ago and I just retested
Borates are now reading about 40 ppm (test strip color is right between the 30 and 50 ppm reading) and this is in line with the Proteam dosing and taking the weight difference needed for borax vs. supreme (.75 by weight of pentahydrate needed to achive the same level as the decahydrate.) the three boxes I put in (14.24 lbs) is pretty much the same as 10 lbs. of pentahydrate which will give me a ppm increase of about 23-24 ppm for my pool. Since I started with a base reading of about 15 ppm and am now reading about 40 ppm this is all in line.

The pH is testing at 7.5.

It's getting dark now so I will let the pool circulate overnight and continue tomorrow. My goal is to reach about 50 ppm borates. I figure it should take me about 1 1/2 to 2 boxes more to do it and maybe another 2-3 qts. of acid.

[waterbear]

restested my water this morning
FC 5 ppm (no change)
CC 0 ppm (no change)
pH 7.5 (no change)
TA 120 ppm (before stabilizer correction) (no change)
TA 97 ppm (after stabilizer correction) (no change)
CH 220 ppm (no change)
CYA 70 ppm (no change)
Salt 3600 ppm (It is hotter today, the pool water is at 92 degrees so this might be the reason for the higher salt reading...once again using the display on the Aqualogic)
Borates about 40 ppm (measured with AquaCheck borate test strip) (no change)


I added 2 more boxes of borax and 1 quart acid.

Restested pH and borates
pH is off the scale so I added another quart of acid and will retest in a bit.
Borates reading a bit higher than 50 ppm but not as high as 80 ppm. I guess 1 and 1/2 boxes would have been perfect. Once I get the pH corrected I am going to turn on the spllover and dump the spa water into the pool. I will let the system circulate for several hours and then recheck the borates. It might be just enought dilution to get me right on the 50 ppm mark!

[Rangeball]

Evan, are the borates supposed to stabilize PH even if alk is high?

[waterbear]

borates will add about 10 ppm increase in TA for each 30 ppm. I did not see that in my pool so far....I will retest TA once I get the pH stabilized. I do not know what effect they will have at high levels of TA. Chem geek might be better able to answer that. My main goal with this is to see if my pH remains more stable and if my need for acid decreases. It will really take a few months of monitoring this to determine if it was worth it.

[waterbear]

Finally got the pH down to 7.4. It took 3 quarts of acid to neuralize 2 boxes of borax. This is pretty much in line with the Proteam recommendation. I have turned on the spillover and will do more water testing late afternoon.

One thing I have noticed is that the water is so clear it actually seems to sparkle. I know this is just subjective but I really can't explain it any other way. Also, the feel of the water is 'silkier'. I suspect that this is because it is closer to the isoelectric point of the human body. I am starting with a salt water pool so to notice a subjective difference in feel is interesting. It actually leaves a 'soft' feeling on the skin when it drys. I guess this is the same effect of bathsalts which often contain borax.

[waterbear]

Retested the water:
FC 5 ppm (no change)
CC 0 ppm (no change)
pH 7.4
TA 120 ppm (before stabilizer correction) (no change)
TA 97 ppm (after stabilizer correction) (no change)
CH 220 ppm (no change)
CYA 70 ppm (no change)
Salt 3600 ppm (once again using the display on the Aqualogic. The pool temp has come down some but since the aqualogic acutally uses conductivity to determine the salt readout the addition of the tetraborates might have caused this 100 ppm increase. I will check a sample with the salt meter at work)
Borates about 50 ppm, perhaps slightly higher (measured with AquaCheck borate test strip) (The dilution seens to have worked!)

I am a bit surprised that I see no increase in TA but then again I started the process with the pH at 7.6 and it is now at 7.4 so that might account for it.

Now it's going to be just monitoring the pH and see if there is any difference in the speed and amount of pH rise over time and the amount of acid needed to correct it. I will keep you posted.

[waterbear]

restested today....all basically the same
FC 5.5 ppm
CC 0 ppm (no change)
pH 7.5
TA 120 ppm (before stabilizer correction) (no change)
TA 97 ppm (after stabilizer correction) (no change)
CH 220 ppm (no change)
CYA 70 ppm (no change)
Salt 3700 ppm (once again using the display on the Aqualogic.
Salt 3700 ppm (salt meter at work)
SAlt 3800 ( Taylor salt test kit)
It is interesting that my salt reading went up since adding the borax. Will have to ask Chem geek about this!
Borates about 50 ppm, Pretty much right on the money! (measured with AquaCheck borate test strip)
Also did a check for nitrates and nitrites....0 ppm for both
phosphates >1000 ppm....off the scale (probaby between 2000-3000 ppm based on dilution results (Hach phosphate test kit, colorimetric)
water is clear, has always been clear, never had algae, never had CC, never used an algaecide!
Since I have no nitrates ro nitrites, phosphates would be a limiting factor for my pool with algae growth... Guess I never had a problem because I keep on top of the chemsitry! Once again I thinik this proves tha chlorine is the best defense at keeping algae away!

Gonna do my daily pH and Cl checks and see how things go this week.