Green Fog in Pool - new user/never posted anywhere....

[leonard]

Ben,

I purchased a Taylor Service Complete Pool Water Test Kit K-2006C. I wish you had mentioned your commission...
I should have it by Friday - or latest on Monday...

Test results this evening:

hard = 500
Tot chl = 1
Free chl = 0.5 to 1
pH is above 8.4
tot alk is above 240
cyn is between 100 and 150

I will add chlorine in a few mins. What do you recommend to lower alk and pH?

Thanks,
Len

[aylad]

Here's the link for how to lower the pH and alk, but I'm thinking Ben will recommend that you finish the shocking process first, because high levels of chlorine will cause your pH to read falsely high..... http://www.poolsolutions.com/gd/lowe...p-by-step.html

Janet

[leonard]

Janet,
Thank you.

Test results this morning:

Hard = 250
Tot Chl = 10

[leonard]

Water is clearing up. Test results this morning:

Hard = 250
Tot Chl = 10
Free Chl = 10
pH = 8.4
Akl = 240
Cyn = 150

Regarding the 12 pounds of green to clean and 4 pounds of yellow-out the pool store directed me to use - are there any residual chemicals left in my pool water? Same question for the polymer clarifiers - what has happened to those chemicals? How do I remove these chemicals?

I have very young children - how do I ensure the water is safe? Is there a specific series of tests that can be done to make sure?

Thank you.

[aylad]

I'll let the chemists in the group chime in, but my thinking is that the chlorine has broken down the other chemicals that you've put in....

Janet

[chem geek]

The polymeric clarifier would have been caught in the filter and then removed by backwashing (since it sounds like you've got a sand filter). That would have also removed most negatively charged particulate matter including some algae. Chlorine would have fully oxidized ammonia, urea, and some other nitrogenous compounds into nitrogen gas and carbon dioxide that will have mostly outgassed. Some other organic compounds will get partially oxidized and remain dissolved in the water. Some others are volatile and would outgas. Many won't react with chlorine and will either remain dissolved (including salts) or will be insoluble so will either form scum at the surface or will have been handled by the clarifier.

The thing to remember is that though algae is unsightly, it is not itself a health hazard (unless there is so much that you can't see the deep end or that it is on surfaces and is slippery). The result of clearing the water doesn't result in toxic compounds remaining. The vast majority are innocuous and in small quantities. There are some disinfection by-products from chlorine oxidation, but the amounts are relatively small and in an outdoor residential pool exposed to UV from sunlight it tends to be minimal.

As for the Green to Clean and Yellow Out, these are sodium bromide products so have essentially turned your pool into a bromine pool. Over time, bromine will slowly outgas from the pool and some brominated organics may get caught in the filter and backwashed, but given how much you've added to the pool that could take quite some time (i.e. years). So when you add chlorine to the pool, it is getting used up converting bromide to bromine -- hence, you've really got a bromine pool right now. 14 pounds of sodium bromide (assuming these products are pure sodium bromide) in 26,000 gallons (40' x 16' x 5.5' average depth) is 64 ppm bromide so not a small amount. That's the worst part of the advice that you were given from the pool store. Now bromine is a sanitizer like chlorine, but it is not protected from breakdown in sunlight so you may find that your chlorine usage goes up on sunny days compared to before. Bromine also smells a bit different than chlorine (actually, I'm referring to bromamine smelling different than chloramines since that's what you smell when bromine or chlorine react with the ammonia from your sweat from your skin).

So your pool is safe, but is no longer a chlorine pool -- it's a bromine pool.

[leonard]

Wife and kids want to go swimming in the pool.

Test results are as follows:

h = 250
tot chl = 1
free chl = o
pH = 8.4
alk = 240
cyn = 150

Is it safe to swim? Or what can I do immediately to modify values to allow swimming.... Please let me know as the kids are chomping at the bit as the pool looks ok

[chem geek]

Your pH is too high so you need to add acid to lower it. Your FC is too low so you need to add chlorine to raise it. You can use The Pool Calculator to figure out dosages though pH adjustment amounts are approximate so you'll add and retest. Your chlorine went away very quickly so you may still be killing off algae, but if you don't stay on top of the chlorine level then algae can come back. Shocking is not a one-time process.

[leonard]

My kids were in the pool over the past few days and the algie has come back and it is turning slightly cloudy....

The test kit arrived and the results are below. Chlorine floater 3" tab dispenser was down to two tabs.... I have since filled.

If you could give me some advise on the next step I would appreciate it. I am adding 5 gallons of 6% bleach at this time..

Thanks,
Len

"0" Free Chlorine
0.4 Chl
7.6-7.8 pH
150 Tot Alk.
370 Calc Hardness
75 = Cyn

[leonard]

After putting in the bleach last night, the pool is now very green and very cloudy. Any suggestions?