Low CH

[robo2k15]

Newbie on the block. Stumbled onto TFP site while researching (wanting to understand) how to maintain my own pool. Anyhow, let me just dive into it.

Here is my testing results as of this morning

FCL 4.76
TCL 4.76
PH 7.7
ALK 82
CH 86
CYA 64

Three weeks ago my CH was at 56. Since then I've been adding "calcium increaser" (approx. a total of 65 pounds to date). According to the label I should be well within my CH range. What am I dong wrong?

PS. I hope this is the correct forum to post my question. I've been learning a lot from the website and a lot more to lean. Thank you for all the info.

 

[jblizzle]

Welcome to TFP!!!

Unfortunately the thing you might be doing wrong is trusting that electronic tester. We tend to not trust them and prefer these Recommended Test Kits.

Using PoolMath, 65 pounds of calcium chloride should have added 413ppm of CH. So clearly your test is not accurate.

 

[Patrick_B]

Welcome To TFP Robo,

I was going to say the same but JB beat me to it. I'm afraid of testing error here as well. That amount of Calcium Chloride ( assuming the product) would have you way higher than 65. One of the suggested kits will be dependable. I would not under any circumstances add more Calcium until you get a better reading.

Perhaps it's different where you are but Low CH isn't usually an issue in CA. Not that I recall your area, so I may be wrong about that. Hopefully I am.

 

[pooldv]

Welcome to TFP. Here are some handy links for your future reference.

ABC's of Pool Water Chemistry
Water Balance for SWCGs

 

[Richard320]

Welcome!

I'm astonished that your CH is so low. The water out here tends to be very hard. You're not filling it from a water softener, are you?

Those numbers look suspiciously like they're from an electronic tester and/or the pool store. I wouldn't trust either one, myself. Take a sample to a pool store that uses drop testing and see what they come up with.

 

[robo2k15]

Just regular water from the tap. Yes, I'm questioning my electronic tester also. I just ordered a TF100 test kit last week, but haven't got it yet. Thanks everyone. I'll post my results once the new kit comes in.

 

[Patrick_B]

Too late now, but there is a TF100 seller in CA. Depending on the day you ordered, it ought to be there pretty soon.

 

[borjis]

Ya I bet your CH is much much higher.

I did some water replacement recently and only needed 45lbs to get it from 60 to 300
and we have the same water volume.

I'd guess yours might actually now be in the neighborhood of around 375-425ppm.

 

[robo2k15]

Received my new TF-100 test kits yesterday. Here are my results.

FC 4.5
CC .5
CH 1450
TA 100
CYA 52
Salt 4200

I tested the CH twice to make sure I get the same reading (1500 for second testing). According to pool math I need to dump 76% of the pool water. There goes water conservation in So. Cal.

 

[jblizzle]

Or see if Reverse Osmosis is available in your area ... although that may cost more than replacing the water.