The Great Tetraborate Experiment!

[Spensar]

Found this link in some old bookmarks. I haven't used them, am not related, etc., but it is an interesting site that sells bulk chemicals, including borax. You can get a 55 pound bag for $1.35/lb. + shipping. Not sure how this stacks up with 20 mule team on sale, but you won't have all those boxes.

http://www.chemistrystore.com/borax.htm

[mbar]

I have used the chemistry store to buy ascorbic acid - they are very dependable, and will even answer any questions you have. The chemicals are delivered quickly too.

[mbar]

Have you tried Lowes? I know they sell it, so you can order it online from them.

[sailork]

I get mine at Home Despot. I think there are some shipping restrictions on the stuff so it might not be so simple to order.

Oh, and I'm pretty sure that swimming pools are the most common usage so look on the "pool aisle."

[waterbear]

Ace Hardware also usually carries it...and you can get it in just about any pool store. In my area one of the pool stores (NOT the one I work at) has the best price I have been able to find....so don't rule out the pool stores, it is possible to shop in one without getting "poolstored"!

[waterbear]

Week 5 and some strange test results! I have not done anything to the pool after last weeks tests except vacumn and put a new cart in the filter so I could soak the old one (It's been in a year and was looking a bit grey...after soaking in Electrosal automatic dishwasher detergent overnight and hosing it off it now looks brand new!)
We did have a few days with no sun and a lot of rain because of Ernesto. The water in the pool is a bit higher than usual but not as high as last week. It's been sunny and hot the past 2 days so there has been some evaporation.

Borates still about 50 ppm....the test strips have division for 30, 50, and 80 and it is between 30 and 50 and much closer to 50 than any other color. I would have to say around 45 ppm. Still within the "good" range and will probably go up when the excess water evaporates.
FC 10 ppm ppm Don't understand this at all....might be from the days with no sun but I just can't explain this!(I lowered my SWG output last week after the test and my FC went UP!)
CC 0 ppm
TC (oto) l10 ppm also, Shotglass method 1:1 dilution
pH 7.6 (rechecked this, Used both Ben's kit and Taylor 2005...it's still holding....5 weeks and I have not put any acid into the pool! don't know if the rains kept the pH down or what)
TA 100 ppm ( was 90 last week, accuracy of the test is 10 ppm so this is basically the same. rains seem to have had no effect on TA!)
Adjusted alk 78 ppm (CYA up to 65 ppm since water in pool is not as high as last weeks test. was 60 ppm last week)
Calcium 180-190 ppm (did test twice, was 170 last week because of dilution from rain, water level in pool a bit lower now)
CYA 65 ppm (up a bit from last week because of water level in pool lower from evaporation)
Salt 3200 ppm (readout on AquaLogic) (temp of water is a few degrees lower than last week and Aqualogic is not temp corrected when it calculates salt level so this makes sense. Guess I should be including the temp readings also...this week 85 degrees, last week 88 degrees.
Salt 3200 ppm (Tayor K-1766)precison of test is 200 ppm so this is essentially the same as last weeks test of 3400 ppm
Pool is still clear and sparkling.
Didn't test the spa this week....got dark before I could get to it. If I get a chance to test it on sunday I will post the results.
The only thing I can't explain is the high FC levels! I have done nothing to the pool except vacumn and put in a new cart last Saturday! Haven't used the pool or spa all week. Perhaps that is part of it and the water is a bit cooler. gonna wait another week and see what happens. Cell in on 6% with an 8 hour run time....might knock a few hours off the run time in a week and see what happens if the FC stays up around 10 ppm.

Can't believe that I have not put acid in the pool in 5 weeks! I still think the rains are what has kept the pH down but during rainy season last year the pool still needed acid every 2-3 weeks! I did have to cut my pump run time down last october to 6 hours a day because it was not so warm and my FC was high....cell output was on 6% then also. This might be what is happening now.

[chem geek]

FC 10 ppm ppm Don't understand this at all....might be from the days with no sun but I just can't explain this!(I lowered my SWG output last week after the test and my FC went UP!)

The largest process of chlorine consumption is the breakdown from sunlight where up to around half of the FC can be consumed each day of full sun. So let's say for sake of argument that you were maintaining 4 ppm FC (your previous reading) and that normally sunlight would consume about 2 ppm of this each day so let's say that your cell was producing 2.5 ppm of chlorine -- 2 ppm for replacing the chlorine broken down from sunlight and 0.5 ppm for oxidation of organics and killing of bugs and preventing algae. If there was little or no sunlight (UV), then if you were in a steady-state of chlorine before, then now you would build up 2 ppm of extra chlorine per day. That's my best guess as to what happened here. Once sunlight returns, the high chlorine levels will get cut down quickly since the same "half-life" rule will apply (so you might go from 10 to 5 or 6 FC in one sunny day).

It's great news that your addition of acid has dropped to virtually nothing, but the borates should only be affecting the buffering of pH and not the actual use of acid itself, except for the reduction in chlorine consumption (and therefore SWCG output, including aeration from hydrogen gas) due to the borates taking over some of the role of preventing algae. So when the time comes when the pH does rise, it will take a lot more acid to move the pH a small amount so that the net amount of acid you have to add might be close to what you used to do per unit time (again, except for the reduction in chlorine production) -- it'll just need to be added less frequently. We'll see if this is true or not...

Of course, you reported in another thread that you found a pH rise even with a solar cover. So we still haven't really figured out the true source of your pH rise yet. I'm still guessing that at least some of it might be chlorine outgassing (perhaps this gets through or around the solar cover or the hydrogen gas bubble aeration still works???) in which case your current lower SWCG chlorine production levels due to the borates taking over some of chlorine's prevention of algae growth will also lower chlorine outgassing due to aeration from hydrogen gas bubbles. As of now, your pH rise is still a mystery to be solved (hopefully).

Richard