New to pool math

You have no signature or other information on type and volume of pool so I cannot provide any guidance on that.
2kg of calcium is nothing. Be sure you have the appropriate information entered for your pool.
 
You have no signature or other information on type and volume of pool so I cannot provide any guidance on that.
2kg of calcium is nothing. Be sure you have the appropriate information entered for your pool.
I couldn’t change chlorine to granules and not liquid. My calcium has always tested fine from the pool shop
 

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That is an odd pH test. Be sure you are doing it correctly.
OP is in AU...that is the AU pH test from clear choice. Redo the pH test. No stir device needed. Two drops, then cap and tilt to mix. Then hold the vial horizontal so the liquid is next to ALL the colors, then match.

On all the tests, fill the vial to the line, THEN put in the stir magnet. If you don't, your volume will be wrong, and test result will be wrong.


Post a picture of the label on the granules so we can see the ingredients. It will be di-chlor, tri-chlor or cal-hypo. Then you can enter that for the "chemical."

Here are the pH numbers from left to right, low to high that match the colors to the numbers low to high (from clear choice). You can hold vial up to screen.
1734659208139.png
 
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Fill out your signature with pool, all pool equipment (include manufacturers and model numbers) and test kit info.
This assists us in providing you help without needing to ask you each time for this important information.

See my signature and Marty's for examples.
If using a mobile device to view the forum, rotate to landscape mode to see signatures.

You won't see chlorine "granules". It's either dichlor, trichlor or cal-hypo. Which type is yours?
 
Pool Math is a bit biased - when you set up the information about your pool it only asks about liquid chlorine or a salt generator. As you get further into the information on this site, you'll find powders and tablets can have problematic long term effects, so tend to be discouraged. For now, just pick liquid chlorine. In the section where you enter results, you can pull down the Sanitizer type and pick the one of the various forms of chlorine sold that you actually use to get the amount you need to add, if any. You'll have to look at the bag ingredients, and any percentage listed (if it is Cal-Hypo).

On the top right is a gear icon to go to overall settings. If you scroll way down, you have the option to link it to your account here, and by clicking on your user name in a post, we can see you logs - so you don't have to deal with screen shots or typing the information. (give mine a try to get an idea of what we will see).

Yeah, it can be a bit much dealing with the start-up stuff here. But you really are in excellent hands. I was an almost 30 yr pool owner before I dove into the methods here. So much good advice, and it settles down and gets easier quickly.

Keep running all the tests a few more times, to get familiar with how it all (the test and Pool Math) works, and confirm to yourself that you are doing them right. There are no "too simple" questions here.
 
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CH being low is rarely a problem, unless you have a newish plaster pool. Most people fight with it being way too high.
Out of curiosity, what has been your routine for adding granules in the past? I assume you've looked at the bag now, and can tell us what kind. Roughly how much, how often?

Run the pH test a time or two more to verify the reading. But if you are anywhere in the 7's, your pool is fine. You can drive yourself crazy chasing smallish amounts with small additions of chemicals.
Right now the important thing is to get the Chlorine up.
Click on the three lines at the top of Pool Math, and select the "Effects of adding". You enter your pool volume, then select the chemical you want to add, and the amount. It will tell you how much that will change your readings. Then when someone says " Add 3 ppm of chlorine" - you can figure out how much of your chemical of choice it will take, by varying the amount.

(I should note that the "Effects of Adding" is all math based, and your pool may have some unanticipated variations in what it needs. For smallish amounts it will be correct, but if it tells you to add a lot of something, it's best to do it in a few batches with testing in between to sneak up on the target. For the 3 ppm chlorine advice, it will be fine to put all it recommends in.)
 
OP is in AU...that is the AU pH test from clear choice. Redo the pH test. No stir device needed. Two drops, then cap and tilt to mix. Then hold the vial horizontal so the liquid is next to ALL the colors, then match.

On all the tests, fill the vial to the line, THEN put in the stir magnet. If you don't, your volume will be wrong, and test result will be wrong.


Post a picture of the label on the granules so we can see the ingredients. It will be di-chlor, tri-chlor or cal-hypo. Then you can enter that for the "chemical."

Here are the pH numbers from left to right, low to high that match the colors to the numbers low to high (from clear choice). You can hold vial up to screen.
View attachment 621896
Thank you I was putting in the water after the magnet was in I’ll retry tomorrow
 

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CH being low is rarely a problem, unless you have a newish plaster pool. Most people fight with it being way too high.
Out of curiosity, what has been your routine for adding granules in the past? I assume you've looked at the bag now, and can tell us what kind. Roughly how much, how often?

Run the pH test a time or two more to verify the reading. But if you are anywhere in the 7's, your pool is fine. You can drive yourself crazy chasing smallish amounts with small additions of chemicals.
Right now the important thing is to get the Chlorine up.
Click on the three lines at the top of Pool Math, and select the "Effects of adding". You enter your pool volume, then select the chemical you want to add, and the amount. It will tell you how much that will change your readings. Then when someone says " Add 3 ppm of chlorine" - you can figure out how much of your chemical of choice it will take, by varying the amount.

(I should note that the "Effects of Adding" is all math based, and your pool may have some unanticipated variations in what it needs. For smallish amounts it will be correct, but if it tells you to add a lot of something, it's best to do it in a few batches with testing in between to sneak up on the target. For the 3 ppm chlorine advice, it will be fine to put all it recommends in.)
I usually put a table spoon of chlorine after use in the pool and tea spoon in the spa and turn in the clean cycles. I usually get the water tested at a pool shop every few weeks
 
Fill out your signature with pool, all pool equipment (include manufacturers and model numbers) and test kit info.
This assists us in providing you help without needing to ask you each time for this important information.

See my signature and Marty's for examples.
If using a mobile device to view the forum, rotate to landscape mode to see signatures.

You won't see chlorine "granules". It's either dichlor, trichlor or cal-hypo. Which type is yours?
Did my signature work ?
 

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I looked up the Vortex information, but it is not clear (and they don't seem to have manuals on line) - does it, at any time, share water between the spa section and the pool section? Or is the water in each completely separate at all times? ie - Can you add water to fill the spa higher than the pool, and it always stays higher, or do they slowly or quickly get to the same level? If they share water, for Pool Math and chemicals, use the total amount (1259+5425 = 6,684). If shared, just treat and do tests on one section. If always separate, then you'll need to treat and test each side separately, and what works for one may be different than the other.

OK then - I had to do math, and I hope I got all the conversions between AU and the US weights and measures done correctly. We'll just use the pool volume (5425) for the following.
For every 10ppm of CL that Dichlor adds to the pool, it raises the CYA level by 9 ppm.

**Edit: hard to find a conversion from weight to tablespoons. I think it really works out to 10gm/tablespoon.
In your case, 1 tablespoon seems to be about 33 10 grams (if I did the conversions correctly). Pool Math's effects of adding says that that will raise your CL by 3.4 1 ppm, and CYA by 3 1. **Edit: since that comes out to be low, you should have been adding about 3 tablespoons. But from now on do it by weight, not volume - so use 35 grams to increase CL by 3.4 ppm, and CYA by 3 ppm. The weight in Pool Math is correct, and maybe not my conversion to tablespoons!

Every pool is different in how fast it uses Chlorine. It depends on amount of sunlight it gets (which breaks down Cl) as well as how much may be used by killing things in the water (algae, bacteria, and many other things). I've seen a pretty wide range posted on this site, but using mine as an example, in summer it may be 3-6 ppm each day. Let's just pretend yours uses 4 ppm for this exercise.

So, adding 35 grams per day, you'll have periods where the CL gets used up and levels fall to 0 during the day. If it is some or more days in between, then a longer time at 0 before you dose it again. If there are things growing in the water (algae, etc), they may use up the added CL almost right away - so even more time at 0 where things could grow.
CYA acts as a reservoir for CL and protects it. Not all of what it "absorbs" is useable for sanitizing, but it will give up some as the Free Chlorine gets used, so helps slow the loss. Our test are only able to test for a combination of the working CL and what is locked up in the CYA (you need a real chemistry lab with very expensive equipment to differentiate, which pool stores don't have either). Hence as you have more CYA, we have to raise the bar as to what amount should be in the pool.

CYA builds up over time, and effectively doesn't go away. If your readings are really so low, I suspect you have only occasionally added the Dichlor. Or it hasn't been very long since you filled with fresh water.

How do you know what yours uses? Test! Add the Dichlor, and after giving a 1/2 hr to mix, do the FC test. Wait until the same time the next day, and test again to see how much it has dropped. If 0, repeat the cycle, using a bit more, until you get a reading the second day. The difference is what you pool currently is needing, to be added each day to keep a given level of CL.

Note that doing the CC test will reveal whether you have things growing in the pool that use up Cl. If the test needs more than one drop, we will have to revisit the subject to recommend a slightly different course of action before you can count on the above to tell you about your pools average use.

If still using the Dichlor, I wouldn't add stabilizer by itself. From the math above, adding only 3 tablespoons a day (35 grams), after 10 days you will be near the previously noted level of 30. What's bad is that Pool Math will tell you to add more and more Dichlor as the CYA raises (which you have to, to maintain an effective level of Cl), which makes the CYA rise faster too. Eventually the CYA gets extremely high, and the only solution is to drain everything and start over with fresh water. Hence the strong preference for liquid chlorine that has no CYA in it. It is OK to use Dichlor to help build up the CYA level to 30, but then switch over to liquid to keep things stable.
 
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I looked up the Vortex information, but it is not clear (and they don't seem to have manuals on line) - does it, at any time, share water between the spa section and the pool section? Or is the water in each completely separate at all times? ie - Can you add water to fill the spa higher than the pool, and it always stays higher, or do they slowly or quickly get to the same level? If they share water, for Pool Math and chemicals, use the total amount (1259+5425 = 6,684). If shared, just treat and do tests on one section. If always separate, then you'll need to treat and test each side separately, and what works for one may be different than the other.

OK then - I had to do math, and I hope I got all the conversions between AU and the US weights and measures done correctly. We'll just use the pool volume (5425) for the following.
For every 10ppm of CL that Dichlor adds to the pool, it raises the CYA level by 9 ppm.
In your case, 1 tablespoon seems to be about 33 grams (if I did the conversions correctly). Pool Math's effects of adding says that that will raise your CL by 3.4 ppm, and CYA by 3.
Every pool is different in how fast it uses Chlorine. It depends on amount of sunlight it gets (which breaks down Cl) as well as how much may be used by killing things in the water (algae, bacteria, and many other things). I've seen a pretty wide range posted on this site, but using mine as an example, in summer it may be 3-6 ppm each day. Let's just pretend yours uses 4 ppm for this exercise.

So, adding 1 Tbsp per day, you'll have periods where the CL gets used up and levels fall to 0 during the day. If it is some or more days in between, then a longer time at 0 before you dose it again. If there are things growing in the water (algae, etc), they may use up the added CL almost right away - so even more time at 0 where things could grow.
CYA acts as a reservoir for CL and protects it. Not all of what it "absorbs" is useable for sanitizing, but it will give up some as the Free Chlorine gets used, so helps slow the loss. Our test are only able to test for a combination of the working CL and what is locked up in the CYA (you need a real chemistry lab with very expensive equipment to differentiate, which pool stores don't have either). Hence as you have more CYA, we have to raise the bar as to what amount should be in the pool.

CYA builds up over time, and effectively doesn't go away. If your readings are really so low, I suspect you have only occasionally added the Dichlor. Or it hasn't been very long since you filled with fresh water.

How do you know what yours uses? Test! Add the Dichlor, and after giving a 1/2 hr to mix, do the FC test. Wait until the same time the next day, and test again to see how much it has dropped. If 0, repeat the cycle, using a bit more, until you get a reading the second day. The difference is what you pool currently is needing, to be added each day to keep a given level of CL.

Note that doing the CC test will reveal whether you have things growing in the pool that use up Cl. If the test needs more than one drop, we will have to revisit the subject to recommend a slightly different course of action before you can count on the above to tell you about your pools average use.

If still using the Dichlor, I wouldn't add stabilizer by itself. From the math above, adding even only a tablespoon a day, after 10 days you will be near the previously noted level of 30. What's bad is that Pool Math will tell you to add more and more Dichlor as the CYA raises (which you have to, to maintain an effective level of Cl), which makes the CYA rise faster too. Eventually the CYA gets extremely high, and the only solution is to drain everything and start over with fresh water. Hence the strong preference for liquid chlorine that has no CYA in it. It is OK to use Dichlor to help build up the CYA level to 30, but then switch over to liquid to keep things stable.
Thank you that is a lot of information I’ll try to answer as best I can

The spa and pool are next to each other but there the water doesn’t go into each other

The pool shop says I need to put chlorine in every day I admit I don’t the guy who did the handover with me for the pool/spa said just make sure I put it in after use and get it checked every so often I used to use the pool measuring sticks but that was hard

I haven’t really looked into liquid chlorine is it a similar price to powder ? Powder is is easy to store as well
 
I haven’t really looked into liquid chlorine is it a similar price to powder ? Powder is is easy to store as well
Make sure when factoring in price and convenience you're including the regular water replacement required to offset the CYA rise from the dichlor. Usually someone using dichlor will have to replace at least half their water every month to keep the CYA level from getting out of control.
 
Make sure when factoring in price and convenience you're including the regular water replacement required to offset the CYA rise from the dichlor. Usually someone using dichlor will have to replace at least half their water every month to keep the CYA level from getting out of control.
I usually replace the water every 6 months or so in the spa side pool shop usually says when it’s due. Can you recommend a liquid chlorine that’s not too expensive? Instead of putting in 30 grams of dichlorvos in how much liquid would that work out to ?
 
Oops! I may have failed in trying to figure out the conversion of the weight of Dichlor to tablespoons! I've edited my above answer to be what I now think is correct. As I added above, trust the weight of the amount to add in Pool Math, and not the volume I may have gotten wrong (even now). I'll use the weight amount in the answer below.
If my conversion is now correct, then you needed three times the amount you had been adding....which would explain the frequent readings of 0.

No idea what may be near you for liquid chlorine. Here in the US, pool stores typically carry it, although they don't advertise it much - since it is a pretty low profit item for them. Many of our big box stores (Walmart, Home Depot, etc) also carry it, at a lower price. Available in 10% or 12.5% strengths. Obviously, you use less of the stronger per time. You may find it at local hardware stores and other similar places, perhaps cheaper than I found. You can use regular grocery store bleach (NO additives, "splashless", color enhancers, or anything else - just plain bleach). But it will be much weaker (typically 6% here in the States), so you'll need twice as much.

This place is one reference I found: https://www.bunnings.com.au/hy-clor-5l-liquid-chlorine_p3090280
And for comparison is their version of what you use: https://www.bunnings.com.au/baracuda-2kg-triple-action-chlorine-2kg_p0388362
So doing the math, the Dichlor is about $0.50 (AU) per 35 grams, while the 12.5% liquid is $0.55 for the 150 ml needed to get the same Cl increase. So a bit more.

Part of the strategy may be how much work it is to drain and refill, and what the cost of the fresh water to do so might be.

Here's a chart showing what your CL level should be at any given CYA level. Aim for the high side of the target range. The minimum is just that - the never go below amount.
You can keep using the Dichlor until your CYA gets to 70, (maybe even push it into the 80's), but then it is time to drain and refill. And as you can see, your target CL level keeps increasing with the CYA level. If doing a drain and refill is easy and cheap, you may just consider doing that when the CYA gets too high. Repeat again later when the Dichlor gets the CYA again high. You may need additional chemicals after a refill - for TA and pH, but those are really inexpensive. (primarily baking soda).
Or if the liquid is easy to get, and the slight cost increase is fine, then you can just keep on with it and not worry about draining and refilling very often. Maybe even years (!)

CYA Chart 2.jpg

Circling back to the CH test - your pool is fiberglass, so no issue with the low CH value. And it is a good thing, as it reduces greatly any build up of hard water deposits in the equipment. It too never leaves the pool, so Calcium Chloride chemicals to increase your chlorine increase CH rather than CYA. Better to just leave alone and enjoy. Maybe test every few months, to make sure it isn't sneaking up on you for some reason.

Again, apologies for the math error, and perhaps sowing confusion!
 
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OP is in AU...that is the AU pH test from clear choice. Redo the pH test. No stir device needed. Two drops, then cap and tilt to mix. Then hold the vial horizontal so the liquid is next to ALL the colors, then match.

On all the tests, fill the vial to the line, THEN put in the stir magnet. If you don't, your volume will be wrong, and test result will be wrong.


Post a picture of the label on the granules so we can see the ingredients. It will be di-chlor, tri-chlor or cal-hypo. Then you can enter that for the "chemical."

Here are the pH numbers from left to right, low to high that match the colors to the numbers low to high (from clear choice). You can hold vial up to screen.
View attachment 621896
Im pretty colour blind i think number 4 so 7.4
 

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Oops! I may have failed in trying to figure out the conversion of the weight of Dichlor to tablespoons! I've edited my above answer to be what I now think is correct. As I added above, trust the weight of the amount to add in Pool Math, and not the volume I may have gotten wrong (even now). I'll use the weight amount in the answer below.
If my conversion is now correct, then you needed three times the amount you had been adding....which would explain the frequent readings of 0.

No idea what may be near you for liquid chlorine. Here in the US, pool stores typically carry it, although they don't advertise it much - since it is a pretty low profit item for them. Many of our big box stores (Walmart, Home Depot, etc) also carry it, at a lower price. Available in 10% or 12.5% strengths. Obviously, you use less of the stronger per time. You may find it at local hardware stores and other similar places, perhaps cheaper than I found. You can use regular grocery store bleach (NO additives, "splashless", color enhancers, or anything else - just plain bleach). But it will be much weaker (typically 6% here in the States), so you'll need twice as much.

This place is one reference I found: https://www.bunnings.com.au/hy-clor-5l-liquid-chlorine_p3090280
And for comparison is their version of what you use: https://www.bunnings.com.au/baracuda-2kg-triple-action-chlorine-2kg_p0388362
So doing the math, the Dichlor is about $0.50 (AU) per 35 grams, while the 12.5% liquid is $0.55 for the 150 ml needed to get the same Cl increase. So a bit more.

Part of the strategy may be how much work it is to drain and refill, and what the cost of the fresh water to do so might be.

Here's a chart showing what your CL level should be at any given CYA level. Aim for the high side of the target range. The minimum is just that - the never go below amount.
You can keep using the Dichlor until your CYA gets to 70, (maybe even push it into the 80's), but then it is time to drain and refill. And as you can see, your target CL level keeps increasing with the CYA level. If doing a drain and refill is easy and cheap, you may just consider doing that when the CYA gets too high. Repeat again later when the Dichlor gets the CYA again high. You may need additional chemicals after a refill - for TA and pH, but those are really inexpensive. (primarily baking soda).
Or if the liquid is easy to get, and the slight cost increase is fine, then you can just keep on with it and not worry about draining and refilling very often. Maybe even years (!)

View attachment 621957

Circling back to the CH test - your pool is fiberglass, so no issue with the low CH value. And it is a good thing, as it reduces greatly any build up of hard water deposits in the equipment. It too never leaves the pool, so Calcium Chloride chemicals to increase your chlorine increase CH rather than CYA. Better to just leave alone and enjoy. Maybe test every few months, to make sure it isn't sneaking up on you for some reason.

Again, apologies for the math error, and perhaps sowing confusion!

That means it’s ok doesn’t it or do I need to add ph up of 20grams ?
IMG_0458.png
 

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