I'm back again!


Well-known member
Jun 25, 2009
Wichita Falls, Texas
Hello everyone!

Last year about this time I was struggling with an extremly high CYA level and mustard algae. Things are a bit opposite this year!

Here are my test results that I did June 2nd:
CYA - 10-20
pH - 7.5
FC - 2.0 ( I kept it this low since my CYA was low...probably not a good idea I know)
CC - 0.0
TC - 2.0
Alk - 70
Calcium - 1400!!!!!!

My pool has been a bit cloudy lately. I did the calcium test TWICE, but I really don't understand HOW it got THAT high. I used some 42% calcium hypochlorite when I ran out of liquid bleach, but I didn't use that much at all.

I noticed yesterday a yellow "film" growing on the bottom of my pool---but the water was still crystal clear yesterday. I brushed the entire pool, and as I did, a yellow cloud would appear where I brushed. Therefore, I assumed I had mustard algae.

An overnight FC test revealed a loss of 1.0ppm cholorine.

I decided to go ahead and begin shocking the pool.

Also, I went to the pool store to have them test my water and they got some different results as me, BUT found my CYA to only be 17.

I bought stabilizer and an o-ring for my pool pump basket and that's it!! They tried to sell me Alkalinity increaser--and I was like...HECK NO! :lol:

These are the numbers the pool store got:
CYA - 17
FC - 9
CC - 0
TC - 9 (I'm shocking the pool so it's high)
pH - 7.6
Total Alkalinity - 81 (isn't this normal? Why are they telling me it needs to be between 125-150???)
Total Hardness (I think that's calcium) - 139

So I need to know what order to attack these minor problems..I am thinking I should go in this order:
1. Adjust CYA to approx. 30 so that the sunlight will not eat up all of my chorline. I am using the pool calulator now to determine how much to put in a sock and let dissolve! :D
2. Redo my calcium test... the pool store got a COMPLETELY different result than me. :(

Any other suggestions?

Thanks for your help! :D



LifeTime Supporter
May 27, 2008
Jamestown, ND
You have a vinyle liner so dont worry about the Calcium test. I have about the same size pool as you do and I dont worry about the CH in my pool. PH is good and TA is fine. 80-120 is the range. PB always have it higher to sell their chemicals in my opinion. I think the CYA and FC is about all you really need to worry about. Good job in not buying the pools chems. Walmart, Lowes ect has the same stuff so good job in resisting their advice.

You are off to a great start.

Good Luck
Keep it up and soon your CYA/FC will be in check.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
TA needs to be higher if you are using trichlor for chlorine, which the pool store will assume.

Your plan sounds like a good one.

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