First numbers with new kit, and boy are they WEIRD!

Jump to latest Follow Reply
Laenini

Laenini

0
LifeTime Supporter
Aug 7, 2008
115
Brooklyn Park, MN
I opened about a month ago with the worst algae bloom I’ve ever dealt with, and I have never gotten the water totally clear yet. I started to suspect my results from my 3 year old test kit could not be trusted, So I ordered a new one and it arrived today. Here are my first numbers with it:
pH (computator) 7.2 and 7.0 from my cool, new pH monitor
FC=40, CC=2, TC=42
TA=130
CYA greater than 100
Ca++ = 625!!
clearly, I need to bring down the CYA and Ca++, so partial water change, correct?
I have been told that in Minnesota we should not empty in ground pools substantially as the ground water can rise up and “float” the pool! So how much can I safely drain? Does anyone know?
thank you!
Leanne
 
With a liner pool, in most areas you can drain down so you leave 18" of water or so in the shallow end. It may take you several iterations of drain, fill, drain, fill etc to get your CYA where you need to be. You need to do the extended CYA Test.
100 is the limit of the CYA test, so you have to do a diluted test. Mix 50% pool water with 50% tap water. Use this mixed sample as your test water. Multiply the result by 2 for your CYA level.
Read Draining - Further Reading. The Exchange method described in the article may work best for you.
 
There's another thread elsewhere on this forum that states that static electricity can sometimes accumulate in transit in brand new test kits making the drop size smaller than normal and leading to higher than expected readings on certain tests, most notably the Sulfuric Acid affecting the reading on the Total Alkalinity test. If your test kit is *brand-new* brand-new and your drop sizes seemed to run on the small side, I would re-run all the tests and give each reagent dropper tip a quick wipe with a damp cloth or paper towel before dispensing, just to eliminate the possibility of static buildup affecting your readings. Good luck!
 
Hey Neighbor!

You could try a no drain water exchange:

Draining - Further Reading

www.troublefreepool.com www.troublefreepool.com

Since you have a heater and assuming fill water is significantly colder than swimming pool water.

EDIT: Oops, I should have known Marty would be on top of the no drain water exchange, I missed that he mentioned it in the very last sentence!
 
I have a second set of numbers now. I carefully wiped to bottle tips to discharge shipping related static energy that might affect drop size, and performed the CYA test with a 1:1 dilution.
pH (meter) 7.3
FC 18
CC 1.5
TC 19.5
CH 450
TA 100
CYA read right at the 100 mark, so that means it’s really 200!
im ashamed to admit that the granular chlorine I though was stabilizer free is actually the same form of chlorine commonly found in pucks, just ground up. I should have known to read the label on the new pail carefully and not assume it was the same as previous pails. Kicking myself all the way outside to start a partial drain and replace.
:hammer::brickwall:
Leanne
In A Box Reaction GIF
 
Laenini said:
CYA read right at the 100 mark, so that means it’s really 200!
Click to expand...
100 on the nose can be tricky. Best to do a 2 part tap to one part pool mix and multiply X 3 to erase any doubt. It’ll probably be close to 200, but still. 200 and 240 is a big enough difference to want to make sure exactly. (y)
 
As you Need to exchange, You need to do a full amount. The exchange has some error. So you will still likely have 40 ppm cya or more after exchanging your entire pool volume.
 
You know what will happen next after this large of a water exchange? I’m going to get a metal precipitate forming. I owned a house with a pool just 3 miles from this house, and the first fill of that pool turned black with an iron or manganese ppt. I’m tempted to order something so that I have it ready just in case. Any recommendations for a good product?
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply