Several questions from a veritable novice

[Yerffej]

I have had problems keeping pool algae-free for last couple of years, luckily I stumbled upon this site. I went to a local Leslie's to get the FAS-DPD kit but they didn't have it. I purchased a "Total Poolcare DPD Test Kit". The results were as follows:
pH 7.5
FC 2
TC 1
TA 130
CYA >100
CH not sure, the kit said it would change from red to blue, but it went from pink to clear somewhere >400 :grrrr:

I drained about 40-50% of the water out yesterday and am in the process of refilling now. What should be my next step? Does the pH need to be in range before chlorine is added? I guess a better question is "Is there a particular order which I should follow to adjust the water", assuming the CYA level is below 50?

Why is the total chlorine less than the free chlorine?

And does anyone know where I can get tan replacement plugs for the holes in the concrete where the childproof fence should be?

Your help is most appreciated.

 

[frustratedpoolmom]

Hi there, unless the ph in your fill water is off, you should be ok to go ahead and add bleach. Be sure to retest the CYA after you have circulated with the new water.

I suspect perhaps a testing error with regard to the chlorine, I would repeat the test. I don't see how FC can be higher than total chlorine...

 

[JasonLion]

Your PH is fine at 7.5.

Most likely TC is lower than FC because you don't have a very good test kit.

When doing the CH test you want to mix throughly for 15 to 30 seconds after each drop. It does get tedious.

Getting PH between 7.2 and 7.8 and adding chlorine are normally the first priorities.

 

[waste]

I have had problems keeping pool algae-free for last couple of years, luckily I stumbled upon this site. I went to a local Leslie's to get the FAS-DPD kit but they didn't have it. I purchased a "Total Poolcare DPD Test Kit". The results were as follows:
pH 7.5
FC 2
TC 1
TA 130
CYA >100
CH not sure, the kit said it would change from red to blue, but it went from pink to clear somewhere >400 :grrrr:

There is something going on with the CL and the CH tests - perhaps one of the other members here can enlighten you as to what it may be

I drained about 40-50% of the water out yesterday and am in the process of refilling now. What should be my next step? Does the pH need to be in range before chlorine is added? I guess a better question is "Is there a particular order which I should follow to adjust the water", assuming the CYA level is below 50?

I doubt you'll have cya of 50, your starting level could well have been closer to 200 however, keeping free chlorine in the pool is important as is maintaining the pH above 7.0 they can be adjusted at the same time with no problems

Why is the total chlorine less than the free chlorine?

It CAN'T be -- TC = FC + CC ALWAYS - the reagents may be bad or you made a mistake with the testing, it happens - there is a 'learning curve' for testing water. With the help you'll get here, you'll be an expert in no time
And does anyone know where I can get tan replacement plugs for the holes in the concrete where the childproof fence should be?

Your help is most appreciated.

Ffej, Welcome to TFP!! You sound like you're on the right path to take control of your pool!!!!! Thank you for doing a little reading here before posting - I know you did 'cause you have the sig line We're gonna be here for you and before you know it your pool will be the envy of the neighborhood :-D

As everyone should, don't forget to re-read Pool School here from time to time - it's a great source for the basics of pool ownership!

Once again, welcome here! Once you get the chemistry right, you should have nothing but a Trouble Free Pool 8)

 

[Yerffej]

Thanks for your responses so far. It had seemed to me that the chlorine was more effective if the pH was within the normal range, but then again what do I know, I was busy poisoning my water with pucks for 7 years.

I also could not see the logic in the free chlorine being less than the total chlorine. Perhaps I should order a TF100 kit.

 

[jjdurrant]

Most (myself included) are going to tell you to invest in the TF100. A nice nice kit is the only way you are going to get an accurate set of numbers.

 

[Yerffej]

waste, you are probably right on the CYA level. Refilling is at least half way done and CYA level is still >100. Maybe I'll get lucky and a hurricane will wash the stabilizer away.

jjdurant, I will consider the Leslie's kit as a emergency back-up and order the TF100.

Thanks to both of you.

 

[Guest]

CH not sure, the kit said it would change from red to blue, but it went from pink to clear somewhere >400 :grrrr:

Why is the total chlorine less than the free chlorine?

Sounds like your testkit was sitting on the shelf for a while and the reagents are bad.
Leslies only sell the FAS-DPD kit online to the best of my knowledge.

 

[Yerffej]

Thanks for your input, waterbear. This makes me doubt every reagent in the kit. At least I hope it's only the reagents. After draining & refilling roughly half of the pool's volume, my CYA is still >100.

 

[Guest]

Thanks for your input, waterbear. This makes me doubt every reagent in the kit. At least I hope it's only the reagents. After draining & refilling roughly half of the pool's volume, my CYA is still >100.

That is probably true. It is not unusual for CYA to be well above 200 ppm or higher. However, it's really hard to test for levels much above 100 ppm. Just keep diluting and you will see it go down. The CYA reagent is one with a fairly long shelf life.

 

[Yerffej]

Hmmm. If the CYA is above 100 after draining half the pool and refilling, why would I want to repeat the process? Assuming the best case scenario of it being 101 (not likely) I would theoretically be close to the normal range after draining half and refilling one more time. But if the level is 140-150 or greater, I would have to repeat this 2-3 more times would I not? 150 would be reduced to 75 with one draining, then to 37.5 with a second dilution right? Two more drainings of half the pool water would be the same as emptying the pool entirely and starting over, would it not? Or am I thinking about this incorrectly?

 

[duraleigh]

Waterbear and virtually all of us on the forum are reluctant to tell anyone to drain their pool completely. The change in pressures are risky but can certainly be done if you wish.

What you might try is to simultaneously drain from the side opposite where you are filling. In that way you could virtually exchange all the water (or get the CYA to an acceptable level) without dropping the level of your pool at all.

 

[JasonLion]

If lower the water level in the pool below the ground water level you can have major damage to the pool. The further you drain the pool the greater the risk, unless you have a way to figure out what the ground water level is.

 

[Yerffej]

Thanks for the safety warning. Seeing as how I'm in Florida, where you can't have a basement because of ground water levels, I should probably not flirt with disaster by emptying the pool. I will do as suggested and drain from the bottom drain and fill in the shallow end. Thanks again.

 

[Guest]

it is ususally safe to do a series of partial drains. You can drain a foot below the skimmer and then refill. repeat this about 5-6 times and then retest the CYA. Repeat this procedure until you get your CY>A down.

 

[Yerffej]

Waterbear, you were exactly correct on your estimate. I had to do 5 more partial drains to bring the CYA level down to 40. The water has been so clear since I got the stabilizer level down and stayed on top of the chlorine level that I have actually been enjoying the pool rather than swearing at it.

Ironically, we just got pounded with 20 plus inches of rain from tropical storm Fay :grrrr: . I could have used that source of water rather than pay the utility company. I see the storm is in your neck of the woods now. Hope you fare as well as we did.