Calculating ppm

[wickflair23]

Ok it probably did a similar job. But there still can be 'old' water to some extent in there. The FC should hold much sooner than when it was all old water.

Questions I just thought of. How long after adding dichlor should I test FC? Container says 5 minutes but that seems fast.

How do you determine how much Chlorine to start with each day? Say typically it's 2 adults for 30 minutes or what if I know I'm having friends over and we might have 4 adults for over an hour. Do I add a bunch of chlorine like 10ppm to handle that bather load?

 

[Mdragger88]

Testing 5 minutes or so after all additions is fine - things get dispersed quickly in a tub.
When manually chlorinating I usually raise fc to around 10ppm after a soak then the tub is around the 6ppm range the following day before the next soak. This is enough in my tub to get me through the next use of 2 people/30 minutes then I do it again.
My tub is small (200 gal) so my bather load is twice as large as the average 400 gal tub. You may not need to go as high to ensure you never fall below min for your cya.
Your frequent testing (before & after use) & during standby times will help guide you.

With my swcg I usually only dose to around 6ppm after normal bather loads as the cell comes on multiple times per day & keeps the fc quite steady.
If the kiddos get in alot (they tend to go back & forth from pool to tub in the shoulder seasons)
or there’s a party
or we long soak I add fc or turn the swcg on after each 30 minutes of use and usually raise to slam level after to help oxidize all the things. Guests often have fabric softener in their suits & lotion on their skin, teen girls use products in their hair & such so those things can chew through some fc.
My tub claims it’s a 5 person but 2 adults is comfortable. However I have had 5 kids/teens in there and that drops fc quickly!

Ps - when you run out of the leisure time stuff get some ahhsome - it may be ahhsomely gross but in a satisfying way!

 

[wickflair23]

Just want to make sure I am on the right track. Been following your advice, but want to transition into bleach soon. I did my first test of CYA which seems to be around 25. I want to keep adding until 30-40, right?

So far I've added just under 4oz of dihcore.


Also, I have some non chlorine shock which I now know I don't need. however, I already paid for it. How should I use it until it's gone?

 

[Mdragger88]

Just want to make sure I am on the right track. Been following your advice, but want to transition into bleach soon. I did my first test of CYA which seems to be around 25. I want to keep adding until 30-40, right?

In the spa? Yes - use dichlor for chlorination until you reach 30-40 ppm cya.
99% Dichlor adds roughly 1ppm of cya for each 1 ppm of fc
I usually do a few slam doses and am finished.
Be mindful of the acidic effects before also adjusting ph.

So far I've added just under 4oz of dihcore.

How many gallons is your hot tub?

Also, I have some non chlorine shock which I now know I don't need. however, I already paid for it. How should I use it until it's gone?

Up to you but there’s really no need if you’re using enough chlorine.
Note* it can show up as cc’s when testing unless you use the taylor interference reagent & can also have an impact on ph. I personally am not a fan & wouldn’t put in my tub/pool if you gave it to me for free.

 

[wickflair23]

How many gallons is your hot tub

410 gallons.

 

[Mdragger88]

410 gallons.

Looks like you’re about there -

Maybe one more dose or so with dichlor then on to liquid chlorine.

In hotter water (above 90 degrees) cya degrades faster so every couple weeks I use dichlor instead of liquid chlorine to keep my cya topped up.
I keep my tub 104 or a little higher sometimes so I do have to regularly monitor cya so i am not accidentally over chlorinating.
The hotter it is the faster cya degrades.

 

[wickflair23]

Looks like you’re about there -
View attachment 598560
Maybe one more dose or so with dichlor then on to liquid chlorine.

In hotter water (above 90 degrees) cya degrades faster so every couple weeks I use dichlor instead of liquid chlorine to keep my cya topped up.
I keep my tub 104 or a little higher sometimes so I do have to regularly monitor cya so i am not accidentally over chlorinating.
The hotter it is the faster cya degrades.

I also have an ozonator does that eat up the CYA?

 

[Mdragger88]

I also have an ozonator does that eat up the CYA?

Nope just fc

 

[Mdragger88]

Ozone Systems - Further Reading

www.troublefreepool.com

Scroll down to the spa part of the article

 

[wickflair23]

Testing 5 minutes or so after all additions is fine - things get dispersed quickly in a tub.
When manually chlorinating I usually raise fc to around 10ppm after a soak then the tub is around the 6ppm range the following day before the next soak. This is enough in my tub to get me through the next use of 2 people/30 minutes then I do it again.
My tub is small (200 gal) so my bather load is twice as large as the average 400 gal tub. You may not need to go as high to ensure you never fall below min for your cya.
Your frequent testing (before & after use) & during standby times will help guide you.

With my swcg I usually only dose to around 6ppm after normal bather loads as the cell comes on multiple times per day & keeps the fc quite steady.
If the kiddos get in alot (they tend to go back & forth from pool to tub in the shoulder seasons)
or there’s a party
or we long soak I add fc or turn the swcg on after each 30 minutes of use and usually raise to slam level after to help oxidize all the things. Guests often have fabric softener in their suits & lotion on their skin, teen girls use products in their hair & such so those things can chew through some fc.
My tub claims it’s a 5 person but 2 adults is comfortable. However I have had 5 kids/teens in there and that drops fc quickly!

Ps - when you run out of the leisure time stuff get some ahhsome - it may be ahhsomely gross but in a satisfying way!

Seems like my tub just eats up FC when not in use. So, my wife and her sister used my tub the other day and my wife didn't add any chlorine after. I got home a few hours later and eventually tested it. No FC. I added about .42oz (last dose. Went higher because of the bather load) of dihcore and then got busy the next two days so I never tested it. Checked it last night and the water is a little cloudy and not clear like it was before. I added about 3floz chorine, but after running the jets realized it was the High efficiency Crud because of the amount of bubbles. Wife still wanted to use the tub, so we both got in for about 20 minutes. I decided to add a .21 of dihcore since I didn't have time to go get more bleach. checked CYA and it's right around 35.

Checked the tub again this morning and still not clear. Did the quick FC test and it did turn light yellow, so there was still some, but didn't appear to be too much. I am assuming this is a lack of FC, but do you have any suggestions? How long does it take for it to clear up? Anything else I should check? Is there like a floater I could use to keep some FC in the tub while not in use or when I am busy?

Thank you for all your help! @Newdude and @Mdragger88 you both have been so helpful!

 

[Newdude]

it did turn light yellow, so there was still some, but didn't appear to be too much. I am assuming this is a lack of FC, but do you have any suggestions

Only use the block test when you're spot checking it's good and yellow. Without any specific value it's vague at best, and CCs are in its TC result, which are higher in a hot tub.

You may have 2 CCs and 0 FC and the block test says 2 TC. So use the powder test until you're at one with the spa and just inherently know how it's going to behave.

I never grasped how nasty we are when I had my tub. I added and added and added like the tests said to, always feeling something wasn't right with the demand. Years later I realized I wasn't enjoying a nice soak, I was making people soup. Residual laundry sauces, hair products, sweat, body oil, exfoliated skin, other nasties that were rinsed off tender areas...... maybe even some hot wing sauce on your fingers and half a spilled margarita and yeah. It's utterly nasty in there and will chew though FC with use, and for some time after use.

 

[wickflair23]

Only use the block test when you're spot checking it's good and yellow. Without any specific value it's vague at best, and CCs are in its TC result, which are higher in a hot tub.

You may have 2 CCs and 0 FC and the block test says 2 TC. So use the powder test until you're at one with the spa and just inherently know how it's going to behave.

I never grasped how nasty we are when I had my tub. I added and added and added like the tests said to, always feeling something wasn't right with the demand. Years later I realized I wasn't enjoying a nice soak, I was making people soup. Residual laundry sauces, hair products, sweat, body oil, exfoliated skin, other nasties that were rinsed off tender areas...... maybe even some hot wing sauce on your fingers and half a spilled margarita and yeah. It's utterly nasty in there and will chew though FC with use, and for some time after use.

Yeah. I have been using the drop test almost every singe time. I was running late this morning so I just did the spot check on my way out to just make sure there was a little something in there. a few weeks ago I tested CC and it was at like .2 or something. I will do a full test tonight. I have my wife grabbing regular (non- HE) bleach today. Also, plan to get my filter out and clean it, but the Dang nut was stuck last night. Always something. Does it sometimes take 48 hours or so to clear back up?

 

[Newdude]

I tested CC and it was at like .2

Use 10ml samples and each drop is 0.5. Nobody was ever saved by the 'pointX'. Save 2.5X the reagents instead with 10ml.

I have my wife grabbing regular (non- HE) bleach today.

Good. Household bleach is 6% or less and it's not that big of a deal in a hot tub needing so little, but still, every little bit helps, right ?

Does it sometimes take 48 hours or so to clear back up?

If FC was too low at any point, yeah. If it doesn't hold FC in two days, (except minimal idle loss) then a SLAM Process is in order.

 

[wickflair23]

Use 10ml samples and each drop is 0.5. Nobody was ever saved by the 'pointX'. Save 2.5X the reagents instead with 10ml.

Good. Household bleach is 6% or less and it's not that big of a deal in a hot tub needing so little, but still, every little bit helps, right ?

If FC was too low at any point, yeah. If it doesn't hold FC in two days, (except minimal idle loss) then a SLAM Process is in order.

I was only doing .2 because it was so Dang low using that @ease system. Thank you for the reminder to go back to .5 SLAM TIME! lol

What is the normal loss at idle? Right now I am seeing about a 4-5FC loss within 24 hours. Assuming because of my UV light system.. ozone or whatever. Is there a float I can put tablets in to have floating around between usage to try to keep the FC up?

 

[Newdude]

I was only doing .2 because it was so Dang low using that @ease system.

I assure you that 0.2, 0.5 and 0.4 all equally suck, no matter what.

Inversely, a 8.2, 8.4 or 8.5 are all awesome for a CYA of 30 or 40. (Etc etc).

What is the normal loss at idle?

Probably 1 to 2 ppm per day. If it's less, never look a stable FC in the kisser.

*but the frog at ease complicates things so YMMV.

Is there a float I can put tablets in to have floating around between usage to try to keep the FC up?

They make 1 inch tabs for hot tubs. Normal CYA jacking rules apply.

 

[wickflair23]

Inversely, a 8.2, 8.4 or 8.5 are all awesome for a CYA of 30 or 40. (Etc etc).

What do you mean by this?

They make 1 inch tabs for hot tubs. Normal CYA jacking rules apply.

Does this mean it uses up your CYA?

I assume during the SLAMMER you don't use the tub?

 

[Newdude]

What do you mean by this?

Those #s were possible results showing the differences between 10ml and 25ml tests. For both, the important # is the one before the decimal point for FC. Whether it's 6.6 with 25ml or 6.5 with 10ml is irrelevant. The 6+ change FC() or the 2+ change FC ( ) is the important part.

Does this mean it uses up your CYA?

Tabs are trichlor which raise your CYA level. It's less of an issue in a hot tub because you dump the water every 3 to 6 months, but still needs to be monitored as the CYA rises so you can target an appropriate FC to match.

I assume during the SLAMMER you don't use the tub?

It's safe and sanitary between min and SLAM for any CYA level.

 

[Mdragger88]

What do you mean by this?


Does this mean it uses up your CYA?

I assume during the SLAMMER you don't use the tub?

Don’t use trichlor in a hot tub - it dissolves too rapidly & very acidic

 

[wickflair23]

Did I screw up here. Took the filters out to hose them off and then ate dinner. Not even thinking about the circ pump still running. Likely wad like that for an hour. Did notice all the small Debris in the bottom of the filtet box is now gone. Darn it.

 

[Mdragger88]

@wickflair23
Just raise to about 10ppm with liquid chlorine for now if they wanna soak a minute then proceed with slam level after they get out - until the tub is clear & cc’s are 0.5 or less.
It is safe to get in up to slam level fc but it can be hard on the suits.
The 10ppm will be gone very quickly anyway if its got alot of bather waste to deal with.
You’re not only making up for the previous waste you didn’t dose for but also all that has proliferated since - & things proliferate rapidly in a hot tub.
Once its clear be sure to dose accordingly in the future. As you can see, making up for a deficit is not a fun game.