So you want to add borates to your pool--Why and How

[susa]

>> risk of the lower borate levels is that it's a nutrient at such low levels, though not usually as limiting as phosphates and nitrates. However, if one is maintaining a proper FC relative to their CYA level, then this shouldn't matter. Somwhere around 30-50 ppm, the algaecidal levels of borates kick in for many algae and slow down their growth.
>>

would low borate (last test at 20 ppm) account for high phosphate (400) reading ? CYA at 40, FC is 5.0, pH is 7.6, TA is 120 and CH is 300

water is crystal clear, even at night and pump runs 24/7 at 900 rpm.

 

[JasonLion]

No, borates and phosphates don't have anything much to do with each other.

In almost all cases you should simply ignore your phosphate reading. It really doesn't matter. Also, not that it matters, but a phosphate reading of 400 is lower than average.

 

[phalcon51]

I haven't had a chance to read this whole thread yet, so if I'm asking something that's already been asked I apologize. I'm thinking of adding borax to our pool which we had replastered last September. Are there any concerns with new plaster in adding the large amounts of acid and borax called for?

Thanks,

Gary

 

[chem geek]

The addition of high levels of salt, be it sodium chloride for saltwater chlorine generators or borax and acid or boric acid for borates should not be done in the first weeks after a new or replaster job. However, after the plaster has significantly cured, around 4 weeks, it is fine to add either salt or borates. Since your replaster was last September, there should be no problem.

Just make sure that you add the concentrated chemicals slowly over a return flow with the pump running, preferably at the deep end. Alternate addition of acid and borax (split the total dosage, say into quarters). Another alternative would be to add boric acid instead which is closer to pH neutral (it's slightly acidic), though that is more expensive.

 

[phalcon51]

It was mentioned earlier that water with borate added can be detrimental to dogs if they drink enough of it. What's considered a lot, any idea? I've got two small dogs, one which spends the day in the back yard. He's about 15 lbs. I have seen him drink from the pool occasionally but I don't know how much he drinks from it while I'm away at work. I keep a one gallon water dish outside for him on the enclosed back porch, with the door open and it's filled with fresh water regularly. Someone mentioned that they trained their dog not to drink out of the pool pretty easily. Anyone have any tips on how to train my dog? I haven't added the borate yet, and don't want to till I feel pretty sure that I'm not harming my dog.

Thanks for any help.

Gary

 

[JasonLion]

If a dog or cat drank 100% of their water from a pool with 50 ppm of borates they would still be below the lowest dose that has any detectable effect, just not all that much below.

 

[phalcon51]

Thanks Jason, good to know. Still looking for training tips though.

Gary

 

[SPKNout4CHRIST]

This may be a crazy question, but as a soon-to-be dad in just a few months I want to cover my bases and am being extra cautious about a lot of things. Would 30-50ppm borates be harmful to a pregnant woman/the unborn child? I have read it is not harmful to humans, but just want to make sure since I know a lot of things change when referring to someone who is pregnant/unborn. Thanks!!

 

[JasonLion]

There is a very substantial safety margin for humans, more than enough for typical government safety regulations to call it safe.

Swimming, in general, is not the safest thing you can do. There are risks, all quite small, but still substantially larger than the risks associated with say watching TV. Swimming with borates in the water is not by any means the largest of those risks.

 

[threewide]

Just did my pool here in Canada. Very easy. What I did was for every box of Borax I added 1 litre of Acid. I added 4 boxes waited about 30-45 mins for residual borax to dissolve in the skimmer. When adding 4 boxes of Borax, I added 4 litres of acid which is right around 1 gallon.
4 boxes of Borax, wait, then add 1 gallon of acid. E-Z!

 

[dsharp]

Just did my pool here in Canada. Very easy. What I did was for every box of Borax I added 1 litre of Acid. I added 4 boxes waited about 30-45 mins for residual borax to dissolve in the skimmer. When adding 4 boxes of Borax, I added 4 litres of acid which is right around 1 gallon.
4 boxes of Borax, wait, then add 1 gallon of acid. E-Z!

4:1 ratio? I just did mine and used 10 boxes borax to 3 gallons of acid (3.33:1) and even then, I could add a little more acid as the pH is now around 7.6 - 7.65 (so hard to tell!) so perhaps 3:1 would be just right for me. Until the pH is a definite 7.7, I'm going to leave it alone. It looks and feels great!

 

[ziflin]

Thanks for all the great information about adding borates!

I was wondering two things:

1. Does adding borates cause any clogging issues with DE filters (or DE filters using FiberClear)?

2. We keep honey bees, and I was wondering if anyone knew of any problems as apparently it kills insects . In the last month that we've had the pool, I've only seen 2 bees land in the water, so I'm hoping that it wont be an issue. They seem to prefer the runoff from the gutters more than the pool. And we're about to give them their own pool .

Thanks!

 

[JasonLion]

ziflin, welcome to TFP!

Adding borates won't cause any long term problems for DE filters at all, but there can occasionally be a temporary issue if you add borates through the skimmer too quickly.

I'm not sure about bees. They should learn not to drink the pool water.

 

[threewide]

4:1 ratio? I just did mine and used 10 boxes borax to 3 gallons of acid (3.33:1) and even then, I could add a little more acid as the pH is now around 7.6 - 7.65 (so hard to tell!) so perhaps 3:1 would be just right for me. Until the pH is a definite 7.7, I'm going to leave it alone. It looks and feels great!

Hmm, did you check your PH right after or did you wait overnight? I checked mine the following day and it has been and still is spot on 7.5. I started with my PH right around 7.3-7.4. I Wonder if water temp can play a part, warmer water tends to dissolve stuff quicker, except for CH. My water was arm numbing cold, around 53F!

 

[JasonLion]

The correct ratio is 3.5 boxes of borax to 1 gallon of 31.45% muriatic acid.

 

[ziflin]

Thanks for the fast response! I did find this mentioning in the Boron EPA study that was posted in this thread:

Boron toxicity in honey bees has also been observed; a concentration of 50 mg boric acid/litre (8.7 mg boron/litre) in syrup had no effect on survival, whereas 100 mg boric acid/litre (17.5 mg boron/litre) caused 50% mortality (Ostrovskij, 1955).

And at the top:

Conversion factors of ppm and mg/m3 for boron:
1 ppm = 0.4421 mg/m^3
1 mg/m^3 = 2.262 ppm

If I did my math right: the 8.7mg boron/liter that was still 'ok' for honey bees comes out to:
8.7mg/L = 8700mg/m^3 * 1ppm / ( 0.4421mg/m^3 ) = 19,678ppm

Assuming the 50ppm boron(it's boron not 'borax' right?) number then 19,678ppm is a whole lot more than the 50ppm in the water .

Or did I get the math wrong? It's been a while since Chemistry class..

Thanks again!

 

[RobbieH]

You would have to do the math in regards to how many mg of boron are contained in the amount of water consumed by the bee. You could have 100% boron, but if the bee doesn't partake, it won't hurt it. On the flip side, if I had 1ppm in my pool and the bee sucked the pool dry, it might die.

 

[JasonLion]

Pool tests are in ppm of boron. 1 ppm = 1 mg/L. So a pool test showing 50 ppm is 50 mg/L of boron or 285 mg/L boric acid.

If I've done my math right the pool water is toxic to bees, the question is will they drink it at all, or will they look elsewhere for water.

 

[ziflin]

Yah, I was a bit confused regarding their ppm to mg/m^3 conversion. If 50ppm equals 50mg/L then according to that EPA test, there would be no effect on bee mortality until the level raised to 100ppm (100mg/L) and that assumes the bees intake as much pool water as syrup/nectar.

The EPA mixed it into syrup, so the bees drank whatever they normally drink during nectar collection. *If* they decided they liked the taste of the pool water (and some people claim they will during dry months), then they would probably drink a smaller fraction of pool water than the EPAs test. What they don't say in the test is how long it took for the bees to die. Were the affected bees able to return to the hive and transfer the syrup to other bees where they may build contaminated wax, feed it to bee larva, etc.

Usually the water itself is enough to kill the bees as they drown in it. So mostly I'd be worried about them bringing it back to the hive and it building up there.

We're not yet ready to add borates to the pool yet, so for now I'll probably just keep an eye on the bees and see how often they end up around the pool. But if anyone else comes across more information on this, please post it.

 

[ziflin]

*Sorry*, I just realized that the 50 mg/liter mentioned by the EPA test was boric acid. The state that 17.5mg/liter of *Boron* was enough to cause 50% mortality.

So if this is the case, 50ppm in the pool is definitely greater than the 17.5ppm required to kill 50% of the bees tested.. Assuming they drank the same amount. Or am I still missing something.