I saw a recommendation to run the pool water through a coffee filter before doing the CYA test, so at least it would *start* clear. Seemed like a good idea.
Algae, Very High pH
- Thread starter cparker5
- Start date
Yeah, that was a part I read and followed too. Not sure it made a huge difference, but my CYA is near 50 with or without coffee filter.
It certainly DOES seem like a good idea but, in reality, it makes virtually no difference. One of the things we stress on the forum is posting advice that is verifiable and accurate. If we don't police that advice pretty carefully, we can end up with these "urban legends" that seem to make good sense but really offer no advantage.
A very similar example is the advice on using a tarp to separate drain water from refill water. I heard that somewhere and decided it was terrific advice so I championed that advice for a year or so until I realized that, in practicality, it was almost impossible to do it effectively in most pools. We have since stopped that advice but we were hardly "experts" in that area.
So, I am hi-jacking just a bit but when you post, make sure you have first hand knowledge of the answer to the question. The accuracy and validity of our answers is what makes us the premier website for pools and will determine if we stay at the top.
Understood, and apologies for passing on advice without first-hand experience. In my defence, I did actually read through what I believed to be the definitive thread on the topic (along with several others) before posting...
http://www.troublefreepool.com/threads/8265-A-discussion-of-CYA-turbidity
... although in fairness on the first read-through I missed the point that in your second simulation (post #17 test two) there was no difference noted between diluting with tap water and diluting with murky pond water. Excluding that missed data point, my take-away from the thread was that :
(a) filtering *did* make a difference for most people, albeit a small difference and from a very small number of people testing
(b) that said, if there was a difference it was sufficiently small as to not really affect the course of action
EDIT -- another point you made (which I didn't consider sufficiently) is that the difference observed from cloudy water is within the normal accuracy limits of the test, and so is even less relevant
(c) there was an open question from chem geek about whether algae and dirt would have the same effect on the test, and general conclusion that testing with actual algae would be a good idea (but since the people most likely to test are also least likely to have algae in their pools I guess this may never happen...)
In this case filtering the pool water seemed like a good way to address the OP's concerns about impact on the test, but in hindsight I agree that I should have at least researched this a bit more carefully before saying anything. I thought I had done so, but your second test in post #17 above definitely argues against the validity of filtering...
So... apologies, and will be more careful next time.
EDIT -- I'm trying to resist the urge to drop my FC levels, let algae start growing, and redo your tests using real algae and real coffee filters
http://www.troublefreepool.com/threads/8265-A-discussion-of-CYA-turbidity
... although in fairness on the first read-through I missed the point that in your second simulation (post #17 test two) there was no difference noted between diluting with tap water and diluting with murky pond water. Excluding that missed data point, my take-away from the thread was that :
(a) filtering *did* make a difference for most people, albeit a small difference and from a very small number of people testing
(b) that said, if there was a difference it was sufficiently small as to not really affect the course of action
EDIT -- another point you made (which I didn't consider sufficiently) is that the difference observed from cloudy water is within the normal accuracy limits of the test, and so is even less relevant
(c) there was an open question from chem geek about whether algae and dirt would have the same effect on the test, and general conclusion that testing with actual algae would be a good idea (but since the people most likely to test are also least likely to have algae in their pools I guess this may never happen...)
In this case filtering the pool water seemed like a good way to address the OP's concerns about impact on the test, but in hindsight I agree that I should have at least researched this a bit more carefully before saying anything. I thought I had done so, but your second test in post #17 above definitely argues against the validity of filtering...
So... apologies, and will be more careful next time.
EDIT -- I'm trying to resist the urge to drop my FC levels, let algae start growing, and redo your tests using real algae and real coffee filters
One last comment -- in my post #21 I was *trying* to say "if you're concerned about the cloudy water affecting accuracy you could do the coffee filter thing to eliminate that concern in this specific case" but what I wrote actually comes across more like saying "this is a recommended practice for general use".
So to that extent, even I disagree with what I typed earlier
So to that extent, even I disagree with what I typed earlier
Well I started to SLAM last night and woke up this morning to a milky blue/green, it looks like progress to me. We'll see
Sorry never got any pics... But it is clear and I can see the bottom.
My numbers today were pretty good so we actually got our first use of the pool.
pH:7.6
FC: 5.2
CC: 0.8
TA: 70
CYA: 47
FC was 5.6 last night and 5.5 this morning
I know that CC number has to come down a bit so I'm still fighting, but no reason to not enjoy the pool.
Thanks all!
My numbers today were pretty good so we actually got our first use of the pool.
pH:7.6
FC: 5.2
CC: 0.8
TA: 70
CYA: 47
FC was 5.6 last night and 5.5 this morning
I know that CC number has to come down a bit so I'm still fighting, but no reason to not enjoy the pool.
Thanks all!