Hi all - sorry if it's a long post.
Short background:
New house, first time pool owner. I'm the type that needs to know the details and maintenance consequences of everything I own. After moving in less than 3 months ago, I've started... diving in... on learning everything I can about pool chemistry. I have a comfortable understanding of relationships of pool properties and causes and effects of different chemical additions. I've lurked on the TFP threads (and learned passively) now long enough. Time for my first question(s).
Some more details:
Upon opening in early June, pool was very green. TA over 210, PH around 7.2 (I bought a Taylor K2005 test kit and have been using that ever since I moved in). Not a good place to start, and not sure how previous owners left it, but not good. Battled lowering TA and keeping PH from cratering for a period of a few weeks, aerating and adding dry acid. Have been using 73% cal hypo as primary chlorine source (recommended by my in-laws, only people close to me that have a pool). Previous owners most likely used trichlor tabs, as they were left behind, along with various fluff chemicals (clarifier, algaecides, and some PH up/down bags.
Pool specs
Struggled at first to get the correct pool volume. After I tracked down the builder/installer, they told me 28,000 gallons. Seemed high. My own calculation comes in somewhere between 16,600 and 18,000, depending how I want to account for the angle of slopes from shallow to deep. Their declaration of 28,000 gallons would be for a 18x36x5.75 (assuming a uniform depth of 5.75, which... it is not). So I can't trust the guy that built it, apparently. Am I safe to just go with about 17,000 gallons for my volume for chemical calculations (I've been adding chemicals based on 16,600, which leads me to further questions).
Second question - I have been adding cal hypo, approximately 8oz per day (evenings), and it seems like I shouldn't need that much, that often. But, I'm new to this, so maybe it's the right amount. Is it reasonable that I should be adding a full 8oz daily?
I know TFP doesn't advocate for cal hypo, due to CH addition, but my CH started at 40 when we moved in. Very low CH in our water supply here, so I'm comfortable with adding the CH for a while, until I get near 200. This leads to next question.
Third question - I've been adding that much cal hypo every day, because my FC level never seems to hold. Overnight, I see losses of FC, which indicates that something organic is present. Water is clear. CC is 0 or less than 0.5 (according to my test kit) every morning. Daily, I see small amounts of what appears to me as dead algae (brownish powder, poofs when disturbed) settling on some vinyl wrinkles or a couple small areas where elevation changes in the slope and circulation can't keep it moving. I've been adding some chlorine also in the mornings, so sanitizer is in there for the family to swim. The OCLT would indicate that I need a SLAM - agree or disagree? The volume question above will help me determine proper volume calculation for liquid chlorine while SLAMming.
One of the suction lines (skimmer basket) has air suction at the elbow right before it gets into the pump. Installer advocated just closing that line, which I did for a while, when pool was still green. Not sure if that caused some sort of rooted algae problem in that line that keeps fueling daily growth and killing off. Since then, I've duct taped the elbow and opened the line. There is some miniscule air intake, still, which has attributed to PH raising slightly more over time, anecdotally, as compared to when I had it closed. I think I should keep it taped and open, until repaired, but if anyone disagrees, I'm happy to hear why. I'm hoping that being able to pass an OCLT (and meet all requirements to end the SLAM) will then allow me to gauge the daily needed dosage of chlorine, via either cal hypo or liquid chlorine.
TFP forums and pool school have been a huge help so far. Still a little overwhelming, learning how to maintain a pool while still settling in after a move, and getting ready for a second kid at the same time haha! Wife is not totally onboard with daily testing and keeping on the numbers. Her parents have a pool that's always visually clear, but they don't test and arbitrarily add cal hypo every couple days, and no other chemicals, so that's what my wife grew up with. Maybe they're lucky that they don't have visible water problems. I can't bring myself to do that. Haha. And knowing what I have learned reading here, I can now see why they have to do pump/equipment maintenance more often than I want to have to do it.
Thanks - sorry for the book.
Gerald
EDIT: forgot to ask - if something organic is consuming FC daily (overnight), should I expect CC to be greater than 0 or 0.5, as it seems to be each day? I've taken water sample to the pool store a couple times just for comparison, and their numbers are all actually pretty darn close to what I'm testing myself. I'm fairly confident in my own testing results, as they have been consistent and I am meticulous with what I'm doing. I'm confused about overnight FC loss, but not seeing a lot of CC (unless my daily cal hypo additions are also oxidizing the CC, but I'm not sure). Thanks!
Short background:
New house, first time pool owner. I'm the type that needs to know the details and maintenance consequences of everything I own. After moving in less than 3 months ago, I've started... diving in... on learning everything I can about pool chemistry. I have a comfortable understanding of relationships of pool properties and causes and effects of different chemical additions. I've lurked on the TFP threads (and learned passively) now long enough. Time for my first question(s).
Some more details:
Upon opening in early June, pool was very green. TA over 210, PH around 7.2 (I bought a Taylor K2005 test kit and have been using that ever since I moved in). Not a good place to start, and not sure how previous owners left it, but not good. Battled lowering TA and keeping PH from cratering for a period of a few weeks, aerating and adding dry acid. Have been using 73% cal hypo as primary chlorine source (recommended by my in-laws, only people close to me that have a pool). Previous owners most likely used trichlor tabs, as they were left behind, along with various fluff chemicals (clarifier, algaecides, and some PH up/down bags.
Pool specs
- located in PA
- Vinyl liner
- 18x36 "sport" pool (from what I've been told, that's the terminology). 3ft shallow on each end, extending about 10 ft from each end. From there, it slopes on all 4 sides, down to an area about 5ft 8in deep in the center.
- 3 suction lines (2 skimmer baskets, two main drain heads in deep center)
- 2 return jets
- Sand filter (model number not in my head)
- Hayward SP2670007X10 pump (installer said it's new as of last year or two)
- Heat Siphon digital heater
- Pool is in full sun all day, and it's been hot here, and seems to heat up very well on its own, when the solar cover is rolled across it
- FC 0 (this morning - 0 or trace amount, daily when tested)
- CC 0 (this morning - maybe trace amount, but less than 0.5 daily, when tested)
- PH 7.8
- TA 100
- CH 140
- CYA < 30 (was around 5 when I moved in, but have added some granular stabilizer, but not enough to get a reading on my test kit which starts at 30, but I think I'm close to mid to high 20s)
- cal hypo 73% (I might have used 40lb already in 2 months - seems excessive)
- dry acid (for lowering PH as needed)
- used a little PH up (is that sodium carbonate?) as needed while lowering TA
- granular stabilizer (about 3lb, total, I think)
Struggled at first to get the correct pool volume. After I tracked down the builder/installer, they told me 28,000 gallons. Seemed high. My own calculation comes in somewhere between 16,600 and 18,000, depending how I want to account for the angle of slopes from shallow to deep. Their declaration of 28,000 gallons would be for a 18x36x5.75 (assuming a uniform depth of 5.75, which... it is not). So I can't trust the guy that built it, apparently. Am I safe to just go with about 17,000 gallons for my volume for chemical calculations (I've been adding chemicals based on 16,600, which leads me to further questions).
Second question - I have been adding cal hypo, approximately 8oz per day (evenings), and it seems like I shouldn't need that much, that often. But, I'm new to this, so maybe it's the right amount. Is it reasonable that I should be adding a full 8oz daily?
I know TFP doesn't advocate for cal hypo, due to CH addition, but my CH started at 40 when we moved in. Very low CH in our water supply here, so I'm comfortable with adding the CH for a while, until I get near 200. This leads to next question.
Third question - I've been adding that much cal hypo every day, because my FC level never seems to hold. Overnight, I see losses of FC, which indicates that something organic is present. Water is clear. CC is 0 or less than 0.5 (according to my test kit) every morning. Daily, I see small amounts of what appears to me as dead algae (brownish powder, poofs when disturbed) settling on some vinyl wrinkles or a couple small areas where elevation changes in the slope and circulation can't keep it moving. I've been adding some chlorine also in the mornings, so sanitizer is in there for the family to swim. The OCLT would indicate that I need a SLAM - agree or disagree? The volume question above will help me determine proper volume calculation for liquid chlorine while SLAMming.
One of the suction lines (skimmer basket) has air suction at the elbow right before it gets into the pump. Installer advocated just closing that line, which I did for a while, when pool was still green. Not sure if that caused some sort of rooted algae problem in that line that keeps fueling daily growth and killing off. Since then, I've duct taped the elbow and opened the line. There is some miniscule air intake, still, which has attributed to PH raising slightly more over time, anecdotally, as compared to when I had it closed. I think I should keep it taped and open, until repaired, but if anyone disagrees, I'm happy to hear why. I'm hoping that being able to pass an OCLT (and meet all requirements to end the SLAM) will then allow me to gauge the daily needed dosage of chlorine, via either cal hypo or liquid chlorine.
TFP forums and pool school have been a huge help so far. Still a little overwhelming, learning how to maintain a pool while still settling in after a move, and getting ready for a second kid at the same time haha! Wife is not totally onboard with daily testing and keeping on the numbers. Her parents have a pool that's always visually clear, but they don't test and arbitrarily add cal hypo every couple days, and no other chemicals, so that's what my wife grew up with. Maybe they're lucky that they don't have visible water problems. I can't bring myself to do that. Haha. And knowing what I have learned reading here, I can now see why they have to do pump/equipment maintenance more often than I want to have to do it.
Thanks - sorry for the book.
Gerald
EDIT: forgot to ask - if something organic is consuming FC daily (overnight), should I expect CC to be greater than 0 or 0.5, as it seems to be each day? I've taken water sample to the pool store a couple times just for comparison, and their numbers are all actually pretty darn close to what I'm testing myself. I'm fairly confident in my own testing results, as they have been consistent and I am meticulous with what I'm doing. I'm confused about overnight FC loss, but not seeing a lot of CC (unless my daily cal hypo additions are also oxidizing the CC, but I'm not sure). Thanks!
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