Cloudy and Confused

[singingpond]

ok my head is spinning again -trying to digest everyone's advice. I will have to say my water clarity is almost perfect at this point. Is there something we are missing.

And I did not SLAM yet. Just replaced 10,000 gal this morning (9 AM) ran filter and tested at 6:00 PM.

I almost did not do the drain as after I brought the chlorine level up (first post) it really cleared up. I brought the chlorine level up with 5 bags of shock and turned chlorinator (frog system) to max for 14 hours. I assumed that if I did not lower CYA I would require that much chlorine all the time.

details details - what should I do next?

I'm concerned about your description of bringing up your chlorine levels with "5 bags of shock" and use of chlorinator. I know that was before you asked questions here and before you did the partial drain, but I want to be sure you now realize that all solid chlorine products carry unwanted baggage. Powder shock is either dichlor (adds CYA, which you want less of, not more) or cal-hypo (adds calcium, which you don't need either). In-line chlorinators use trichlor tabs (adds CYA).

In the future, you should be using liquid chlorine (e.g. bleach) when you chlorinate. Otherwise your high CYA problem will quickly get worse again.

edited to add: Reading earlier posts, I see I'm just reiterating what several other posters have said. It's important, though, so I suppose repetition doesn't hurt

 

[jfuredy]

Do this experiment. Simply take a sample of pool water and put it in the CYA view tube. Do you see any cloudiness or can you read the black dot clearly?

There is virtually never any affect. If you really are able to obscure the black dot with just pool water (doubtful) then simply subtract that value from your normal CYA result.

I'm not sure if this was directed at me, the Original Poster, or both, but I'll reply anyway. I would love to be able to do this test, but my water is now crystal clear, so it won't tell me anything useful.

On my drive home from work yesterday I also thought about trying this test as well, but I wasn't sure if the results would be additive. Say the plain pool water tested at 30ppm CYA, would it be accurate to just subtract this 30ppm from the actual CYA test to get your "real" CYA value?

But you also make a good point that it may not be a factor at all. If the second or third step is obscured, that's what, 18-24" of water depth. And the sample vial is only 3" deep? I'm just trying to figure out why my readings were so much different than what I expected/thought they were.

 

[Swampwoman]

Given our already high cya rate, going forward please consider chlorinating with liquid, which doesn't add cya, instead of powders and sticks, which DOES add cya

So when you did this:

I brought the chlorine level up with 5 bags of shock and turned chlorinator (frog system) to max for 14 hours.

the irony is that you were increasing the very cya that you were draining to reduce

If you keep using the sticks and powdered form of chlorine, you will keep having to retest cya and adjust FC upward to keep water clear and clean.

The alternative is to add liquid chlorine daily or as needed now, using he Pool Math calculator and the CYA- Chlorine link (clck on it to see chart) to get your routine set up. If you stop adding products with cy, you won't ave to test the cya very often, eg maybe monthly or so.

Glad you're in te clear and hoping to hel you stay that way

 

[chem geek]

On my drive home from work yesterday I also thought about trying this test as well, but I wasn't sure if the results would be additive. Say the plain pool water tested at 30ppm CYA, would it be accurate to just subtract this 30ppm from the actual CYA test to get your "real" CYA value?

But you also make a good point that it may not be a factor at all. If the second or third step is obscured, that's what, 18-24" of water depth. And the sample vial is only 3" deep? I'm just trying to figure out why my readings were so much different than what I expected/thought they were.

You are correct in what you wrote that IF you were to see the black dot obscured at 30 ppm with plain pool water (i.e. before any reagent is added) then you'd subtract that from your reading when doing the CYA test with reagent mixed in. However, as you point out, you'd have to have VERY turbid water for this to be the case since the tube is not very deep. This is why the turbidity of the pool water itself is hardly ever a factor in influencing the CYA test. What a few people have seen is that algae or particles in the water may give a falsely higher reading not from direct turbidity but somehow influencing the melamine-cyanurate precipitation to appear more cloudy or otherwise obscure the black dot more. This is not a common occurrence and certainly one that has not been explicitly reproduced/verified/understood so normally one does not need to worry about it.

 

[jfuredy]

Thank you for the confirmation, chem geek.

And I would like to sincerely thank you for the work you do on this site. Not only for your obviously strong technical knowledge, but also for your willingness to share that knowledge with others. Being a chemical engineer, I don't feel like I'm done learning something until I truly understand the underlying how and why of it. And your posts are answering pretty much all of my questions before I even have to ask them. Thank you!

 

[sljozzie]

OK another 10,000 replaced - added 64 oz LIQUID CHLORINE
and 18 hours later my numbers are:
FC = 3
CC = 1
TC = 4
CH = 225
TA = 160
CYA = 30 - 40 (closer TO 40)

Pool is clear (a couple of small white patches need to sweep, but 99.9 % better)
I think I am good unless someone sees another problem.

Thank you for all the help!!

Next project: Automatic solar cover reel

 

[Megsyperk]

I think that CC shouldn't be above .5 but wait for someone more knowledgeable than me to come along. Your FC is on the low end for a CYA of 40.


Sent from my iPad using Tapatalk

 

[Crackerjack4u]

Meg, I'm kind of a newbie here too, but I tend to agree the CC of 1 is suspicious that something unwanted is lurking in there, and may need to be stopped.
I'm concerned that the white patches could be algae trying to bloom.

sljozzie You might want to Raise your FC level to at least double from target, so target is 5 for a 40 CYA level, so raise and maintain it to at least 10ppm, preferably 12ppm, at all times, 12ppm is Your SLAM/SHOCK level. Do this for a few days, frequently rechecking your FC, CC, levels (hourly if possible, but no less than 2 Xs daily), to see if you can't get kill off what's in there and get that CC to drop below .5, and be able to pass all 3 criteria of OCLT.


Criteria of OCLT

1)less than 1ppm of FC loss overnight (not sure this part actually has to be done Overnight with an indoor pool or not, you may be able to check OCLT anytime since you don't have the sunlight as a factor but to be on the safe side, until someone tells us differently, just go ahead and check it as an overnight drop.

2)CC of less than .5ppm

3) crystal clear water.


With all the new water you've added doing this Now should help prevent a full blown algae bloom of whatever is lurking below, and shouldn't take long to rid your pool of whatever it is in there that's combining with your chlorine. So I suggest you go ahead, hit it Early with the high FC levels, and get that crud out of there.

Keep us posted on how things are going, also run the pump 24/7 if possible, brush a couple times a day, and vacuum often. Check your steps, skimmers, returns, lights for hidden algae and clean if found. Have a wonderful day.