This Newbies Learning Thread

[happipoolguy]

Hi All,

Our pool went in a few weeks ago (it's our first ever!).

Latest test results (as of this morning)

FC: 9.98
CC: 2.1
PH: 7.6
CH: 209
TA: 103
CA: 22
Salt: 4340

Granted these are pool shop results however my Clear Choice Labs test kit arrived yesterday, so I'll be able to check regularly from here on in.

I've had a read through Pool School and the other resources but am still tentative about what step to take first.

Pool is crystal clear, so I assume I need to start bringing the FC down closer to 6, yes? Would appreciate some guidance on where t from here. TIA

 

[pooldv]

Welcome to TFP!

Test your CYA with your clear choice test and then set your chlorine level based on the [FC/CYA][/FC/CYA] And your CYA.

For a saltwater pool here is what you are looking for, Pool School - Water Balance for SWGs

But, since it is probably starting to cool off down there it will be time to shut off the SWG soon and switch to bleach. I normally turn off my SWG when the water drops below 65-70°F or 18-20°c.

 

[happipoolguy]

Welcome to TFP!

Test your CYA with your clear choice test and then set your chlorine level based on the [FC/CYA][/FC/CYA] And your CYA.

Cheers mate. I did that yesterday afternoon but couldn't get a reading. I guess that's because the test kit measures 30-100ppm and based on the pool shops results I may be light on for CYA. Am I better off bringing CYA up to 60 before trying to balance with FC?

But, since it is probably starting to cool off down there it will be time to shut off the SWG soon and switch to bleach. I normally turn off my SWG when the water drops below 65-70°F or 18-20°c.

Yep, winter's here... a great time for a pool install hey

That's the first I've heard about switching of the SWG during winter. What's the reason - to avoid over chlorinating? (is that a word??)

 

[pooldv]

It's a word here on TFP. Yes, go ahead and add 30 ppm of CYA and see where you end up. Most SWGs have a cold water shut off temp. Well, now you've got a little time to mess with the pool and you'll be all set for spring!

 

[happipoolguy]

Well, now you've got a little time to mess with the pool and you'll be all set for spring!

True that. Will look to boost the CYA tomorrow.

I ran a couple of tests this afternoon using the new test kit and it was interesting to see significantly different Chlorine results when compared with this morning's Pool Store numbers.

Pool Store FC = 9.98 Test Kit = 17
Pool Store CC = 2.1 Test Kit = <.5

Is this a normal phenomenon?

 

[Jezza]

Yep that is pretty normal in terms of the difference between a pool store reading and one with a recommended test kit ie- the CCL kit you have and the one you should work from. What is your CYA reading?

 

[happipoolguy]

What is your CYA reading?

Jezza - When I tested CYA with the kit I could not get a reading (i.e. the little black symbol stayed visible). The kit says it measures CYA between 30-100ppm accurately. Anything less than 30ppm will not show a result. The Pool Shop test showed CYA at 22ppm, therefore I'm assuming that's why I couldn't get a result with the home kit.

If I'm reading this right, Pool Math says I need to add approx 3.7L of liquid stabilizer to reach this target.

 

[Jezza]

Yes if it is still visible then it is less than 30. Before you go adding too much CYA in you just need to consider whether you are going to switch the SWG off for winter. If you are going to do that and then just use liquid chlorine you don't really want to go any higher than 50 CYA. In which case I would add 10 CYA at a time then re-test to make sure you don't overdo it.

By the way we suggest adding CYA by using the granulated stabiliser because it is half the price. You just stick the granules in an old stocking/long sock and hang in front of a return to dissolve it.

Where in Queensland are you- you might be able to keep the SWG running all year around anyway?

 

[happipoolguy]

I wasn't planning on turning the SWG off, simply because no-one's mentioned it before now (keeping in mind up to finding this forum, I'd only received advice from installer & pool shop). I'm located west of Brisbane (in Ipswich) - what's happens if you run the SWG during winter?

 

[Jezza]

Often when the temperature reaches about 10-15 degrees the SWG will stop generating chlorine but I don't think it will be a problem for you. Most SWG's have an indicator of some sort to let you know that the water temperature is too cold.

 

[happipoolguy]

Ok thanks mate. If nothing else I now know to keep an eye on it.

I'll pick up some stabiliser from Bunnings tomorrow and "borrow" a set of the missus' stockings to hang 1kg in front of the return pipe.

 

[Jezza]

All good. Now your FC is a bit high. You might just want to dial the SWG right down. As you add your CYA up to 70 or 80 then you'll want your FC to be around 7 or 8.

 

[happipoolguy]

SWG dialled down to zero last night. I'll check FC this afternoon before re-adjusting.
700g of Stabiliser currently working its way through the system. I know I'll probably need something closer to 2kg but I'd hate to overshoot the mark!

 

[Jezza]

 

[happipoolguy]

FC: 12.5
CC: .5
PH: 7.2

Dropped 500ml of acid in this morning as well, so this afternoons results suggest I hit the mark there.

With the SWG off for almost 24hrs looks like I've consumed (burnt off?) approx 4.5ppm in FC. Is that normal?

I'll let the CYA settle in overnight and take a test tomoz.

 

[Jezza]

Yep with little CYA- very normal.

Also the higher above your target FC for your CYA level then the greater will be the chlorine loss. FC also generally reduces daily as a percentage of the starting level.

 

[happipoolguy]

Ok. Latest results are as follows:

Results from poollogger.com

FC: 10.5
CC: .5
PH: 7.4
TA: 150
CH: 275
CYA: 35
Temp: 16
Salt: 4300

I'm hoping someone can validate or correct my thinking here.

a) maintain the SWG at 0% to keep the FC on the downward spiral.
b) PH keeps creeping up because TA is too high. Do I simply need to keep adding acid and aerating until TA falls into line?
c) Buffer added has moved the CYA needle. Add another 700g to keep pushing it toward 70
d) For some reason CH increased since last test (although the last result was pool shop, this result is home kit) - not sure what I need to do here??

TIA

 

[Jezza]

Ok. Latest results are as follows:

Results from poollogger.com

FC: 10.5
CC: .5
PH: 7.4
TA: 150
CH: 275
CYA: 35
Temp: 16
Salt: 4300

I'm hoping someone can validate or correct my thinking here.

a) maintain the SWG at 0% to keep the FC on the downward spiral. Yes
b) PH keeps creeping up because TA is too high. Do I simply need to keep adding acid and aerating until TA falls into line? Yes you can do or just let your pH ride up to 7.8 and then add acid and repeat as required. You should notice that your pH rise will slow over time
c) Buffer added has moved the CYA needle. Add another 700g to keep pushing it toward 70 Yes
d) For some reason CH increased since last test (although the last result was pool shop, this result is home kit) - not sure what I need to do here?? Nothing needing to be done here. It's in the recommended range.

TIA

I've addressed each of your questions above

 

[happipoolguy]

I've addressed each of your questions above

thanks a tonne mate. Appreciate the feedback!

 

[happipoolguy]

After dropping another 700g of buffer in this morning the CYA was right up there this afternoon.

FC: 10
CC: 0
PH: 7.2
CYA: 80

80 seems to be the recommended level for a SWG so hopefully it doesn't continue to rise overnight.

I also tried a salt test with the kit for the first time (the readings so far were from pool shop). The result I got was 6000ppm - surely that's not the case and I've somehow made a mistake!?

Noob Query: When doing a titration test it says to mix after adding each drop. If you know the approximate range of your water is it OK to add the bulk of the agent, then mix, then go drop (and mix), drop (and mix) as your approaching the likely result?

For example: if I know my FC level is approx 10, can I add 14 drops of the reagent (then mix), 1 drop (then mix) and so on until I achieve the reaction?