Trying to Increase Calcium

ecsii

Active member
May 10, 2019
31
Fresno, CA
I have been trying to get my calcium hardness in the correct range with my TF-100 kit. I have everything in the correct ranges except CH. It started out 120 and I have added 75 pounds of Calcium Chlorate and it has only risen to 150 and the test chart says it should be between 250-400. When I stated it said to add 40 pounds and I ended up adding 45 lbs. only went up to 125 . Tested again it suggested 35 lbs which I didand it went up to 150. Am I doing something wrong?
 
Welcome to TFP! :wave: If we assume you are having no difficulities wiht the actual CH test itself, adding calcium should increase CH. The only reason I can think of that would explain why CH is not increasing, or perhaps even lowering, would be a water leak. Do you suspect a leak, or do you use an autofill by chance?
 
I do add water once a week. Don't have autofill. I'm in the San Joaquin Valley of California and it gets pretty hot and I have quite a bit of evaporation. Although the last couple of weeks have been realatively cool around mid 80's. I have no leaks that I'm aware of.
 
Depending on which product you added (calcium chloride versus calcium dihydrate), 75 lbs is a lot and should've increased CH to 415 or 350 respectively. If we rule out a leak, then it falls back on a testing issue. Which water sample are you using when using the TF-100 (10 or 25 ml sample), and do you also use a magnetic speedstir? Lastly, are you waiting until you see the "baby-blue" color of the reagent (not purple).
 
This is the SpeedStir. Makes a huge difference. But even when hand mixing, for you to not see any significant CH increase after adding all that calcium is odd. I'd review those instructions one more time to be safe (especially the math part) as we ALL gotten those mixed up before. :crazy: Make sure it's not somethingt right in front of you. The last thing I would want is for you to keep dumping calcium into the pool if not needed, especially if your local water is hard. An elevated CH is generally something we worry about quickly in the southwest areas.
 
That's exactly why I am confused because I know our water is very hard and I have always had a problem with calcium deposits on my tile ( I just changed to this TFP process).
In that case, I would hold-off on adding any more calcium until you are sure what the root porblem is. I'm going to give you a couple video below just in in case. Let me know if this helps you at all. Last thing I just thought of ... what product did you add? Do you have the brand/product name avaliable?

 
Ok. I watch the Video and Check the water out of the tap. I checked it once before but don't remember what it was now, no memory. I will get back to you after wards. Thanks for the help, I really appreciate it!
 

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That's exactly why I am confused because I know our water is very hard and I have always had a problem with calcium deposits on my tile ( I just changed to this TFP process).

Maybe, maybe not it depends on where exactly you live and the wells (or surface water) that supply your water.
Test your fill water as suggested.
What type of filter do you have? Do you back wash regularly?
Fill out your signature when you get time as it helps folks here diagnose your issues.
 
I backwashed the filter and added new DE. I ran the filter Thursday, Friday, Saturday, Sunday and Monday and retested 10 ml of pool water. It turned red and it only took 6 drops of R-0012 ( 6x25=150) to change it to blue. Also tested the tap water it took only only 3 drops of R-0012 to change to blue. Guess the water isn't as hard as I thought. I just don't understand this though because my pool tile has heavy calcium deposits and faucets and shower heads also get calcium deposits. The Sodium Chloride I used was Polar Thaw Coated Granular Ice Melt and Bare Ground Coated Salt Cal Pellets that I bought at Lowes. Do you think I need to add more Sodium Chlorate?
 
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Just to confirm .... I think there may be a couple typos in your last post:
"Also tested the tap water it took only only 3 drops of R-0012 to change to red." - You probably meant blue correct?
"The Sodium Chlorate I used .... " - Maybe you meant calcium chloride?

Either way, if you are using the 10 ML sample size with 10 drops of #10, 3 drops of #11, then using #12 drops until baby blue, that's your CH level. With no leak, the only other thing that can contribute to a test error would be using old reagents or products that weren't stored in a cool/dry place away from direct sunlight. The Magnetic Speedstir I posted above can also help, but hand stirring won't be off by hundreds of ppm. If your CH level is still low, it may time to increase a bit. Perhaps increase part of the way then consider using Cal-Hypo for a week or two which will increase FC and CH. That was you can monitor CH levels slowly. Just a thought.
 
Yes my test kit is new. I have only had it since about November 20th. Yes and I did mean blue not red. I keep the test kit inside my house. I think I will try a different product I see there is a product called Cal Plus. It is more expensive than the Calcium Chloride I used before but maybe it may be more pure. Forty pounds is $51.11 instead of $35.00.
 
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Also won't the Cal Hypo cause my CYA to increase? I'm really trying to keep that under control. I was using the 3" chlorinating tablets and the CYA would go up so much that I had to drain my pool twice in 2 1/2 years. That is the biggest reason I change to this process to get that under control. I have it a 30 now and just don't want to have to drain my pool again. So I am watching it really closely and only put tablets in when the CYA drops down below 30.
 
Also won't the Cal Hypo cause my CYA to increase?
No. Just calcium. The other tablets with Trichlor or Dichlor are the ones that were increasing your CYA. You can also see those effects on the Poolmath APP under Effects of Adding Chemicals.
 
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