I've tried to avoid posting a questions thread..

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NWscott

0
Sep 1, 2011
10
Portland
Fantastic site, I have learned everything i know now, from the "Pool school"

As much as i don't want to ask.. i have to!
My pool has been up for 5 days now, I bought the $20 HTH 6 way kit from wallyworld.. instead of using the Intex test strips..

this mornings test shows
FC -0
CC -0
pH - 7.8
TA - 120/140 (right in the middle IMO)
CH - 20
CYA - 0

I have run the saltwater pump for 8 hours a day, 4 days.. there is 175lbs of salt in the pool, and when the SWG is on, there are a decent amount of airbubbles on the side of the pool..

The water is crystal clear.. It smells like chlorine.. but i get Nothing back on the Chlorine tests, I have read that i could add more salt.. Or even add bleach.. 1 gallon of 6% bleach will add 6ppm to a 10,000 gallon pool.. well, i only need 1-2ppm in 7000 gallons.. so i would start with half a bottle?

I understand i need to add CYA.. that's my next move.. but i wanted to post first!

Also, Is there a problem with only 20ppm of CH? should i raise it? how far?
 
Welcome.. :D

I can't really answer about the SWG as i know nothing about them yet. Sorry on that. How often and when are you testing? For a 7000 gallon pool you'll only need about 5 cups of bleach to raise it to a FC level of 3. That's the top range for a pool your size. You are correct the next step is to add some CYA. Once you raise that level you'll alter the amount of FC you'll need, but you'll keep more in the pool daily. Here's the pool calculator to help you out some.
http://www.poolcalculator.com/

Somebody should be able to help out with the SWG, but for now.....welcome to the site. :D
 
With no CYA, your swcg is working overtime and all the fc is being eaten up by the sun... you need to have approx 70ppm cya with a SWCG. with a vinyl pool i donot thnk the CH will be an issue. but you could use calhypo to add fc and calcium, or you could use trichlor to add fc and CYA... and ensure you have the correct amount of salt in the water for the SWCG.
 
Welcome to TFP!

Ask away, that's what we're here for :~}

You can use the pool calculator to determine exactly how much bleach to add. Measure your water level though, and then use the volume calculator at the bottom of the pool calc to get your exact volume. Intex gives volume based on an unknown water level (I haven't found the level referenced in any of their material) and an inch more or less makes a few hundred gallon difference in volume in nearly all their pools.

The reason your SWG can't keep up right now is very likely due to the lack of CYA. So yes, add that as soon as you can. But right now it's very possible that you need to shock the pool so do not add more than 20-30ppm worth (for now) so if you do need to shock, it will take less chlorine. CYA for the Intex SWG is 60-80ppm, many people report that 60ppm does just fine so you can start out conservative and then if needed, raise it by 5-10ppm incrementally if 60 doesn't seem to work for you.

The walmart 6 way has no ability to test for CC, so don't expect it to. However, you can add the FAS-DPD kit from http://tftestkits.net and you'll then have everything you need. I'd also recommend getting more CYA reagent from TFTestkits because you'll need to test that more than one more time (HTH only has two CYA tests). If your pool smells like chlorine but reports none... it's probably combined chlorine that you're smelling instead. Any chlorine your SWG is producing is being eaten rapidly, which produces combined chlorine. If you had the testing equipment available, you might see CC but the HTH kit can't show that to you.

CH for a SWG is listed at 50-200 or something like that. I take that to mean it should be at least 50ppm, so unless someone here says not to worry, a little calcium for the pool is in order (see pool calculator).

Make sure to enter your pool volume into the pool calculator at the top, and then set the goals section at the bottom to TFP and vinyl pool.

I think if I were you that I'd shock the pool anyway. 5 days without adequate chlorine is a recipe for an algae bloom. I had one bloom in a perfectly balanced pool when I let it fall below minimum ONE time. It can git ya fast...

I'd turn off the SWG, add 20ppm CYA and raise the pool to shock level (11ppm) and keep it there for at least today and tomorrow. You can fudge by diluting the OTO test 3:1 with distilled water and attempt to test hourly with that to be able to maintain shock level. It's not as accurate, and can't really be used to do an overnight loss test but it's better than nothing if you want to shock right now. Getting the FAS-DPD test on order however will improve your chances of success considerably and you'll be able to perform an OCLT (overnight chlorine loss test) sooner than later. Depending on where you are located and if you order today, you could have it by Saturday via USPS (TFTestkits is in NC).
 
NWScott,

They've given you good advice, I'll just add my personal experience. The HTH 6 way I got earlier this summer ended up having 3 CYA tests in it. Once you add the CYA don't bother checking it for about a week, it may or may not show up. 24 hours after adding it plug in the amount you targeted into the pool calculator and add chlorine as if it was there. If you'll put the CYA in an old sock and hang it in front of the return it'll dissolve faster, you can also give it a squeeze once or twice a day. I've not had an algae bloom so the 6-way and TFP has gotten me through the summer. Next year with the new to me pool we're setting up I'm getting the TF100 test kit. This year's pool has been an excellent starter and proof of use pool, and an inexpensive way to learn.
 
The HTH 6-Way is an OTO test (yellow). I can't hardly stand to use it personally. I do not like yellow, it's hard to color compare with. The Taylor DPD (R-0001 and R-0002) was much easier to read and it does not bleach out till over 11ppm or higher.

That being said, there is little to no reason to ever recommend the Taylor DPD even if a pool or spa is indoors (little to no CYA for indoor pools so FC is usually well under 5ppm) or for those with SWG who can maintain low FC levels(<5ppm). The FAS-DPD is clearly superior to color block tests, there's little room for error when you're looking at clear vs pink tint as an end value indicator, and half or less of a scoop of DPD powder should be plenty to turn it hot pink with low FC levels. One FAS-DPD kit will last a long time if you only use 2-10 drops per test. Plus, .5ppm is nearly impossible to judge when using a block that graduates in 1ppm increments.
 
Now is the time to begin a pool log. Record all the info on your pool and then begin recording water tests and what you do in response. What you add and what you expect. Over time that will be a great help in managing the pool. I am amazed at how poor my memory is about when the pool was last tested for TA or CH or when the temp was warm enough to swim.

Meanwhile, proceed as instructed above.

Your pH is fine, keep between 7.5 and 7.8, TA is high but mostly self correcting as you maintain pH in that range.

Tend to CYA and FC right away. I find the HTH brand of stabilizer is faster to dissolve than the type I got at a pool store but the normal sources for HTH (Walmart, Lowes, Ace Hardware) may be switching out their seasonal stocks so that may be harder to find. Other varieties are fine, just harder to dissolve. You will add the CYA (in a sock) and then shock to kill off anything that may have started growing in the pool as directed above.

After that, when testing shows that you are done with shocking, you will let the FC level drift down. After that, you will need to adjust the SWG to keep FC where you need it. Quite likely you will need to turn the SWG down, maybe way down.
 

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4 hours.. 8 responses.. I think it's safe to say, my pool water wont be killing me anytime soon!

Yesterday, my PH was low, and my TA was like 20ish.. so we used a calculator and added 10lbs of Baking soda.. that put the TA at 120ish.. and brought the PH up to between 7.6-7.8

I saw some advice to another member, to test the FC directly infront of the return, while the SWG was running.. This gave me results of TC: 4

So, I'm pretty sure we'r on the right track! I LOVE the Pool calculator.. that is GENIUS!!! you CANT get any easier then that!

I will add the stabalizer (CYA) today, and run the SWG for 8-12 hours and retest tomorrow..
 
If you've got FC in front of the return, but not elsewhere, it's being consumed too fast for the SWG to keep up. That non-zero result only proves that the SWG is working, NOT that sanitation is adequate!

Also, if you can smell chlorine, that's usually CCs. Which is additional evidence that something's growing. I'd suggest an OCLT if you had a test kit which would do it. Ordering an FAS-DPD from tftestkits would be wise, as frogabog suggested.
 
I just realized you're the PDX guy!

Now I know why your CH is so low. The tap water is like 2ppm CH, and TA was 10 last I checked. PH is 8-8.2 from the tap, the city does this intentionally. Our water is also pre-algaed. I'm convinced of it and I've seen the source firsthand twice. It's clean and clear... but no different than any other reservoir or lake... algae is inherent. I can see the green at about 4" when I fill my pool. I recommend shocking new fills in this town.

Before you go buying calcium, I've got a massive bucket of it over at my dad's house in Laurlehurst and I'm more than happy to share if you want. I'll never use it all, nor will dad. PM me if you want to do this, I can have him leave the bucket on the porch for you if he's not going to be home. Calcium is hard to find here in small quantities because vinyl pools don't need it and the inground ones that do are much larger than any vinyl. H bought the calcium before we found TFP, as we were previously using mainstream information about pools and thought we were supposed to have some in the pool. I know... duh!

You don't need much of the calcium, I'd say calculate for 60-70ppm and expect to loose some via splashout and refilling. You might have to raise it next year if you leave the pool up but I've been waiting all summer and splashout has only lowered CH to 20ppm, down from 50 in the spring. We had raised it manually to something like 200 last year, then found TFP and drained 50% to lower CYA a week after filling. The CH has taken two seasons to get as low as it is now. I don't know the science behind the SWG and calcium. I asked once in another thread but I don't think it was ever answered specifically. I am going with the 50ppm minimum when and if I ever hook my SWG up so I need to add a little now as well.

If you're nearby I could probably come by and run a FAS-DPD test for you and check for CC. TFTestkits is fast to ship, but it's still a whole continent away so it takes a week to get here. I drive a suburban however... so anything over 6 miles costs me a whole gallon of gas... each way. Closer is better for me.
 
Sorry, I wish i would have waited :hammer: , I picked up 4lbs of Calcium chloride, aswell as 4lbs of CYA..

Yesterday Evening, I added 2lbs of Calcium, aswell as 2lbs of CYA..

Retested 12 hours after, (this morning) and my new readings are as followed


TC-0.5
pH - 7.4
TA - 120
CH -50
CYA - 20 (estimate, tube only shows 30ppm-160ppm? and at the very very top, i could no longer see the black dot..)


30 minutes ago, I added 2lbs More CYA, aswell as 36oz of 2.75% bleach.. (all i had in the house) I plan to get the CYA level up to 70-80 range, and bring the TC up to 4 by using bleach.

I also still have the intex test strips, I have not been relying on these(reports say not to), but i do test the FC level with them, I just realized that TC and FC are not the same.. so even though both tests are netting the same results.. I need to focus on them separately???
 
Read the ABC's of Pool Water Chemistry article/post at pool school. Total Chlorine measures the active chlorine (the amount of chlorine fighting some kind of battle) against the free chlorine (inactive chlorine). The active chlorine is the combined chlorine, it should be less than .5ppm. To measure CC use TC - FC = CC. This is why the FAS-DPD test is recommended, it can not only measure chlorine above 5ppm, but also shows combined chlorine (CC). When/if CC is over .5ppm, organics are beating the chlorine up and shocking the pool is in order.

Strips are junk unfortunately. Been there done that, never to go back again. The inaccuracies are too far and wide to use them to adjust chemicals, and never would I trust a TC/FC reading looking for >.5ppm CC.

Also, don't test the CYA for another week, you only have two CYA tests in the HTH kit and it often doesn't register right away (although my experience differed, I tested the day after adding it this year and got a valid result. HTH brand CYA.) Use the pool calculator and once it's all dissolved, expect it to be in the pool and chlorinate according to what you know you have added.

Too bad on the calcium... oh well. You know where to get more if you need it :~}
 
That confuses even me.
There are only two actual chlorine MEASUREMENTS. FC, or Free Chlorine, is what is available to sanitize your pool. CC, or Combined Chlorine, is chlorine that has actually combined with some organic substance and has done it's job. It has moved from the 'Free' roster to the 'Combined' roster. TC, or Total Chlorine, is simply the sum of both. So FC is needed to sanitize, CC is 'used', and TC = FC + CC.
 
The way I've understood it is that chlorine isn't actually used, until it's gone. I very well could be wrong, I have been many times before. But until the CC off gasses into the air, it's still in the pool which means it's active and battling something. My understanding is that CC is always being produced as a result of the disinfection process. When there's nothing to disinfect, you'll see a 0 CC result. When it's working on something, CC indicates this and once it's finished, it will off gas and then disappear. At that point I consider the job "done".

If CC is finished with it's job already, and FC is free (waiting to be used or burned off by the sun)... where in the test measurements is the chlorine that battles?

Sorry if I confuse or make false statements. If I'm completely out in left field on this, clarification would be great.
 
I'm not sure.. I know i want to pick up a kit from tftestkits.net But i just cant justify it with only having a month left of the season..

I have however, re-tested.. and i tested TC with my hth KIT, aswell as FC with the intex test strips (Iknow..Iknow)

FC:3 (test strip)
PH:7.6
TA:120
TC:2
CYA:40
CH:50

When i run a TC test infront of the return with the SWG on, I now get a strong 5..
 
NWscott said:
FC:3 (test strip)
TC:2
Click to expand...

See the above? This is why those strips can't be relied upon. TC is never less than FC.

You have everything you need except the FAS-DPD test and more CYA tests with that HTH kit. TFTestkits has a stand alone FAS-DPD kit as well as a massive bottle of CYA reagent that you could add to your HTH kit and probably use all next year without needing to order any more reagents. I'd actually recommend buying the reagents alone and a scoop instead of their kit because you already have a cylinder. That'll save about $6 making your FAS-DPD portion about $20. CYA in 8oz (a lot!) is only $7.50.

(I secretly use my old HTH kit in this manner, but I also have the Taylor reagents as backup. I like the graduated cylinder from the HTH kit, very swirl worthy)

If you're impatient like I was earlier this season, you can go to Norflow out in Clackamas and buy R-0780 DPD powder for $15.75, plus R-0871 2oz for about $13, and R-0003 1oz for something like $8 and have the same thing as you would by ordering through TFTestkits. I didn't purchase CYA reagent there, I have plenty. I spent far more than I would have if I had ordered through TFTestkits. Then I spilled my whole $16 bottle of DPD powder and ordered from TFTestkits anyway cuz theirs is only $6.75! (I got two).
 
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