Why would R-8 turn water red and not green?

[PoolGuyNJ]

I opened a pool today. 2 drops R7 then 5 of R-8 and the water tuned pinkish red like a chlorine test. I have never seen that before. CL is 0 and pH is no more than 6.8 . Will an extremely low pH cause this?


Scott

 

[Melt In The Sun]

Yup, if it's below 4.5 or so (Richard could tell you exactly). TA is zero and extremely low pH.

 

[taekwondodo]

Seen it! A couple of times... most recently just two days ago on a vinyl lined doughboy.

Low, low pH, and zero TA. Tons and tons of leaves on the bottom (tannic acids? I know when I used to raise discus (an Amazonian tropical fish) this was one way we used to lower pH and TA). Oh, turning green and CYA was >>>100, too!

- Jeff

 

[chem geek]

Yup, if it's below 4.5 or so (Richard could tell you exactly). TA is zero and extremely low pH.

Yup. That's it exactly. This is one of those times when a pH Up product (sodium carbonate or Arm & Hammer Super Washing Soda) is useful since you want to raise both pH and TA. [EDIT] The amount of pH Up or 20 Mule Team Borax you would use as well as baking soda depends on the actual amount of carbon dioxide still left in the pool at the low pH. If all the carbon dioxide is driven out of the pool, then it's 1.38 pounds of pH Up with 9.22 pounds of baking soda OR 2.60 pounds of 20 Mule Team Borax with 10.26 pounds of baking soda per 10,000 gallons. If instead there is carbon dioxide left in the pool, then the amount of pH Up or 20 Mule Team Borax required can be a lot higher and the baking soda can be less -- such as 4.1 pounds of pH Up with 4.8 pounds of baking soda OR 7.8 pounds of 20 Mule Team Borax with 7.9 pounds of baking soda.

So the real rule is just to use either pH Up or 20 Mule Team Borax to get the pH up to around 7.2 and then use baking soda to bring the TA up the rest of the way (which will raise the pH a little as well to get closer to 7.5 which I assume is the target). With baking soda, 22.4 ounces (1.40 pounds) weight raises the TA by 10 ppm as does 14.15 ounces (0.884 pounds) of pH Up as does 51.3 ounces (3.21 pounds) of 20 Mule Team Borax (though obviously the latter two raise the pH a lot). [END-EDIT]

 

[PoolGuyNJ]

What I find confusing is how, with a solid cover, did this pool get down that low. Water was clear and the bottom not too bad. New customer too so no history available.

Thanks guys. Its not often I am the one asking.

Scott

 

[JasonLion]

Those always seem to be people using trichlor tablets who haven't thought about raising PH or TA in a long time.

 

[waste]

Its not often I am the one asking.

Scott

It's a shock to the ego, isn't it?

What makes ~ all the "In the Industry" posters here different from the majority of pool dudes out there is that we come here to both help pool owners and also learn the better ways of caring for pools, so that we can do our job better

For folks like you and I, this site is an invaluable resource because it gives unbiased (sales driven) advice, especially on the chemistry side of pools (THANK YOU Richard, especially, et. al.) It also allows folks like you and me to pick up a trick or 2 from each other.

IMO - what we do here sells more pools and helps keep us in business/ working better than the NSPF!

I know you're really busy right now and feel for you

 

[taekwondodo]

Its not often I am the one asking.

Scott

It's a shock to the ego, isn't it?

What makes ~ all the "In the Industry" posters here different from the majority of pool dudes out there is that we come here to both help pool owners and also learn the better ways of caring for pools, so that we can do our job better

For folks like you and I, this site is an invaluable resource because it gives unbiased (sales driven) advice, especially on the chemistry side of pools (THANK YOU Richard, especially, et. al.) It also allows folks like you and me to pick up a trick or 2 from each other.

IMO - what we do here sells more pools and helps keep us in business/ working better than the NSPF!

I know you're really busy right now and feel for you

You're on the money with this post - I've found this site to be invaluable to my business and education outside of the "NPSF" and other associations who really think chucking tabs is pool care.

Oh - And I just got back from a "new prospect" less than 20 minutes ago. Green pool. He's been a tablet guy for years and years. He's been chucking in CalHypo and Dry Acid in his pool trying to solve his problem - and HIS T/A was at zero (and Ca almost 800... and still green water). I expected very high CYA (in the hundreds), but it was at 50... looks like the algae and bacteria have been at work.

 

[chem geek]

I've corrected my post since the calculations didn't include the needing baking soda and also made some incorrect assumptions about the starting TA which really has to be negative since the amount of carbon dioxide in the water would be way too much out of equilibrium to be realistic (i.e. outgassing would occur over time as more acid is added so carbon dioxide would leave the pool to a fairly low level). This requires baking soda to get the TA up.