View Full Version : Getting Calcium Levels Right
jmarcum
03-08-2016, 07:37 PM
I have a midnight blue, 10,000 gallon, gunite pool that is 2 years old. It's had turned completely white or maybe I should say whiteish gray from calcium buildup. I drained it, acid washed it an refilled it. I'm taking this opportunity to use the knowledge that I've learned on this forum. I've removed the tablets from the chlorinator and I'm not planning to use any pool store chemicals if I can help it. The pool has an ozonator and I know many of you on this site don't like those but in my experience it works great. I'm able to keep my chlorine levels incredibly low and keep crystal clear water. From now until swim season I'm mainly concerned with keeping my calcium levels good so that I don't start getting build-up again. I'm also keeping my acidity high to help with that. My question is what is a good calcium level and how should I accomplish that? My initial water test 24 hours after filling the pool came back as follows. (since the chlorine was non-existent I added two gallons of publix brand outdoor bleach after taking this sample)
CH-100
PH-8
CYA-0
TA-50
FC-0
FormerBromineUser
03-08-2016, 10:11 PM
Have you tested your full water, especially for CH?
Also, have you added CYA?
Boo on the ozinator...
jmarcum
03-09-2016, 10:45 AM
I did not test the fill water. Should I?
I have not added anything other than some bleach. I didn't want to do ANYTHING without consulting you experts first.
I really don't know why you guys hate ozonators so much. I've read all the posts on this about them but my experience with it has been nothing short of fantastic. Over the winter I let my pool sit for months trying to see how long it would stay clear with no chemicals (other than the chlorine tabs) and the ozantor and it stayed perfectly clear the entire winter. I suspect it would have done the same even without the tablets.
FormerBromineUser
03-09-2016, 10:53 AM
You want your CH to be somewhere around 250-300. If your fill water is high in CH, you should aim for the lower figure as topping off your water level will increase your CH.
Did you add CYA yet?
FormerBromineUser
03-09-2016, 11:00 AM
You want to use calcium chloride or calcium chloride dihydrate. Other products can affect pH and TA.
jmarcum
03-09-2016, 11:00 AM
I have to assume since my pool is currently at CH-100 that must be the fill water level. I'll test it today to confirm. What is the recommended way to increase CH? I have not added CYA yet. Didn't want to add anything until coming here for advice on how to do it right.
jmarcum
03-09-2016, 11:03 AM
From the pool store?
swimdaddy
03-09-2016, 11:43 AM
Are you testing with your own kit or using the poolstore? Here it is recommended you get a Taylor K2006C and test yourself. If you don't have it, order it on Amazon and in the meantime get yourself an HTH 6-way kit from walmart and use that until it comes.
jmarcum
03-09-2016, 11:45 AM
I'm testing it myself. I have a Taylor test kit. I've been using that for 1 year now.
FormerBromineUser
03-09-2016, 01:32 PM
Yes, you can get it at a pool store. Many people cheap-out and get ice-melt and other types but they can contain other metals that you do NOT want in your pool. I would go with a product made specifically for pools if it was my pool. I would start with 8 pounds or so and see where it takes you.
jmarcum
03-09-2016, 01:50 PM
I was able to get pure CYA (Clorox brand) and CH up (Also Clorox brand) from Walmart. I bought 4 pounds of the CYA and 15 pounds of the CH. According to the container each 1 pound of CYA raises 12,000 gallons by 10ppm. Each pound of CH up raises CH by 10 ppm in 10,000 gallons.
Currently I show my CH at 100 and CYA at zero.
Would you agree that it's safe to add 2 pounds of CYA and 10 pounds of CH... wait 24 hours and test again?
FormerBromineUser
03-09-2016, 04:39 PM
That looks pretty good, however, I wouldn't bother testing CYA again for at least 4 days or so. It takes a while before it will show up accurately on a test and you definitely don't want to overshoot on either CYA or CH.
jmarcum
03-09-2016, 07:13 PM
On a completely unrelated note, maybe I should start a new thread but... I'm noticing that two of the jets that send water back in to the pool from the filter don't look right. Typically the water entering the pool is almost undetectable however from two of the jets the water appears to be mixed with a lot of air. I hadn't noticed this before today, of course I also haven't been looking at the pool over the winter. Could this be indicative of some type of issue? Here's a video of what's happening. https://www.youtube.com/watch?v=NJDn1QeIIns
FormerBromineUser
03-09-2016, 08:57 PM
Oh my. That's a lot of air.... Is there any air in your pump basket? Have you lubed your o-ring lately? Do you have a bleed-valve on your filter? I am not very good at pump stuff and will see if I can get someone to chime-in.
jmarcum
03-10-2016, 07:13 AM
There is something that appears to be a pressure release valve on the top of the filter. I'm not sure what O-ring you are talking about but I've not lubed anything.
FormerBromineUser
03-10-2016, 08:17 AM
Well, I would try the pressure relief valve for sure. I always turn mine on after I get any air into the system, usually after I clean the pump basket.
The O-ring is inbetween the pump basket and its clear cover. As they start to get old, some pool lube (not vasoline), helps. Eventually they need to be replaced so that you can get a good seal.
jmarcum
03-10-2016, 10:32 AM
Thanks, I will try those two things when I get home today. I have some food grade lube that is used to lube the seals on my margarita machine, I'll confirm it's not petroleum based and use that. LOL
swimdaddy
03-10-2016, 11:30 AM
Its normal to have some air on the pressure side on start up and after depressurizing to clean out the basket, but without a continuous feed of air it should eventually stop as the air is pushed out. If the air bubbles are continuous, then you have air being sucked in on the suction side, either at a fitting from the skimmer to the pump or the pump basket. You should be seeing air bubbles in the pump basket. The O-ring is the first thing to check, then check all you fittings and lines for air leaks.
Your pump could also be cavitating if there is a constriction or blockage on the suction side. Make sure the skimmer basket is clean and valves are all open, and the lines are clear of debris.
mas985
03-10-2016, 02:31 PM
A pump should not lose prime when it is off. So the only time you should see air out of the returns on start up is if you have solar. On solar drain air fills the lines and that needs to be purged on startup again. However, that should stop after a few minutes. So if you don't have solar, then it is likely an air leak on the suction side of the pump.
Also, to correct a misconception, when a pump cavitates, it does not produce air out of the returns. It produces water vapor in the impeller which then quickly collapses within the impeller as pressure rises so no net air is produced out of the pump.
jmarcum
03-10-2016, 08:59 PM
You guys are amazing! I greased the O ring, cracked the pressure relief valve, closed the ozonator ran the pump a few min and and this is what it looks like afterwards: https://m.youtube.com/watch?v=6nP1wJ0Xftw When I turn the ozonator back on and close the pressure release valve I do get a tiny bit of air bubbles but I think that's to be expected since the ozonator injects air into the pump. Even then there's 95% less bubbles than the first video I posted.
FormerBromineUser
03-10-2016, 09:55 PM
Woot!!!! I can't tell too much from the video, other than I don't see bubbles?! Awesome! How are your plans for CYA and CH doing?
jmarcum
03-10-2016, 09:56 PM
You're right... no bubbles! It started raining really hard here today so I'm waiting a couple more days to test the water again.
FormerBromineUser
03-10-2016, 10:01 PM
No worries. You have to wait to test that CYA anyway. Can you test your pH ASAP, though? It was high before...
jmarcum
03-11-2016, 06:33 AM
I'm running it high on purpose. I'm hoping that the high acidity will help prevent the buildup issue. I'll lower it when pool season arrived
Doesn't high pH encourage scaling?
When you say "high acidity", you mean high pH, right? High acidity would be low pH.
jmarcum
03-11-2016, 06:47 PM
I'm probably totally confused as to how Ph relates to the amount of acid in the pool. I want more than normal amounts of acid. Is that lower Ph? I thought it was higher Ph. :-(
The lower the pH, the more acidic the water becomes. The higher the pH, the more alkaline it becomes. pH of 7 is neutral.
https://simple.m.wikipedia.org/wiki/PH
FormerBromineUser
03-11-2016, 07:28 PM
Great posts, JimK!!!! jmarcum, don't go lower than 7.2.
Great posts, JimK!!!! jmarcum, don't go lower than 7.2.
+1!
FormerBromineUser
03-12-2016, 07:51 PM
So, jmarcum, did you lower that pH? Don't feel bad. We all have been there!
jmarcum
03-13-2016, 07:11 PM
I lowered the ph....now it takes 6 drops of R-0006 to get up to 7.0.
TA: 40
CH:250
CYA:35-40
Up to 7???
I hope you didn't drop your pH below 7 (7.2 is the lowest I would go). Doing so risks damage to your pool.
jmarcum
03-13-2016, 07:16 PM
Yes, as in its under 7.0. Trying to determine how much baking soda I need to add now. :-(
jmarcum
03-13-2016, 07:18 PM
Seems like it's actually borax I need not baking soda. Is that right? I don't know how to calculate this because I don't know what my ph actually is (since it was completely off the charts low)
Seems like it's actually borax I need not baking soda. Is that right? I don't know how to calculate this because I don't know what my ph actually is (since it was completely off the charts low)
Yes, you use borax to raise pH.
Here's a tool you can use to calculate doses
http://www.troublefreepool.com/calc.html
You may have to initially estimate your pH and go from there. Try raising pH a little at a time instead of trying to do it in one shot.
jmarcum
03-13-2016, 07:34 PM
Thanks, I have their iOS app. From an estimated 6.5 it says add just over 5 pounds. How about if I add 2.5 pounds and test again tomorrow?
Thanks, I have their iOS app. From an estimated 6.5 it says add just over 5 pounds. How about if I add 2.5 pounds and test again tomorrow?
That sounds reasonable.
FormerBromineUser
03-13-2016, 07:56 PM
I would suggest testing tonight after a couple of hours of circulating the borax if you can. Low pH can be tough on your equipment and yours needs to come up to 7 or 7.2ish.
jmarcum
03-13-2016, 08:59 PM
I probably haven't let the water circulate long enough but after 2 pounds and roughly 1.5-2 hours I'm dead on 7.2. I say dead on but as you know testing without sunlight is hard. Under my kitchen floresciants it looks like 7.2
I probably haven't let the water circulate long enough but after 2 pounds and roughly 1.5-2 hours I'm dead on 7.2. I say dead on but as you know testing without sunlight is hard. Under my kitchen floresciants it looks like 7.2
Good. Retest tomorrow morning if possible to see if that's accurate. If it is 7.2, at least you're out of the "danger zone".
Btw, since you have a plaster finish pool, you'll want to pay attention to the CSI number in the link I provided.
FormerBromineUser
03-13-2016, 10:34 PM
So glad you are at 7.2! Always be conservative with additions. Better to undershoot than overshoot!
So glad you are at 7.2! Always be conservative with additions. Better to undershoot than overshoot!
+1
FormerBromineUser
03-13-2016, 11:06 PM
^+1
jmarcum
03-14-2016, 09:33 AM
Should I bother trying to raise my TA? It's currently 40.
Should I bother trying to raise my TA? It's currently 40.
If your pH stays stable and your CSI is good, then I wouldn't worry about your TA number. I suspect though that you may end up needing to raise it some.
jmarcum
03-14-2016, 06:07 PM
PH holding steady at 7.2
When I plug all my numbers into the calculator the CSI say -0.91 -0.52. That seems to be indicative of something bad but I'm not sure what I'm supposed to do to fix it.
http://i272.photobucket.com/albums/jj163/jmarcum01/Capture.jpg (http://s272.photobucket.com/user/jmarcum01/media/Capture.jpg.html)
Toybuilder
03-19-2016, 09:30 PM
I'll throw in my two cents for what it's worth.
From what I was told (by chem geek), your CSI should be between -0.3 and +0.3. I try to shoot for the middle of all the recommendations on that page. For your setup I would probably go with:
FC - 3 or 4
pH - 7.6
TA - 80
CH - 300
CYA - 40
Assuming no SWCG and with a temp of 65 your CSI would be -.11 which the calculator will tell you the water is balanced. If your water ever got up to 100, your CSI wold be +.19 which would still be balanced. Right now with the current numbers you've input, "Corrosion of plaster is likely". If you go the other way and your CSI is +.3 or greater "Scaling is possible".
I played with that calculator quite a bit to figure out what would be best for my spa and for the pool. Seems to be working out pretty well for me.
Figure out what works best for you and then try to hold those numbers.
Hope I didn't over step my boundaries. Good luck!
I'll throw in my two cents for what it's worth.
From what I was told (by chem geek), your CSI should be between -0.3 and +0.3. I try to shoot for the middle of all the recommendations on that page. For your setup I would probably go with:
FC - 3 or 4
pH - 7.6
TA - 80
CH - 300
CYA - 40
Assuming no SWCG and with a temp of 65 your CSI would be -.11 which the calculator will tell you the water is balanced. If your water ever got up to 100, your CSI wold be +.19 which would still be balanced. Right now with the current numbers you've input, "Corrosion of plaster is likely". If you go the other way and your CSI is +.3 or greater "Scaling is possible".
I played with that calculator quite a bit to figure out what would be best for my spa and for the pool. Seems to be working out pretty well for me.
Figure out what works best for you and then try to hold those numbers.
Hope I didn't over step my boundaries. Good luck!
I would add to be careful not to go too low on the FC. 3 is at the lowest end recommended for your CYA; it leaves no room for error. I'd shoot for mid recommended range, so about 5ppm.
jmarcum
03-19-2016, 09:58 PM
I'll throw in my two cents for what it's worth.
From what I was told (by chem geek), your CSI should be between -0.3 and +0.3. I try to shoot for the middle of all the recommendations on that page. For your setup I would probably go with:
FC - 3 or 4
pH - 7.6
TA - 80
CH - 300
CYA - 40
Assuming no SWCG and with a temp of 65 your CSI would be -.11 which the calculator will tell you the water is balanced. If your water ever got up to 100, your CSI wold be +.19 which would still be balanced. Right now with the current numbers you've input, "Corrosion of plaster is likely". If you go the other way and your CSI is +.3 or greater "Scaling is possible".
I played with that calculator quite a bit to figure out what would be best for my spa and for the pool. Seems to be working out pretty well for me.
Figure out what works best for you and then try to hold those numbers.
Hope I didn't over step my boundaries. Good luck!
I don't understand how to change the CSI though. Are you saying if I hit all the all numbers the CSI will just fall in line?