New Pool, New TFP member, posting numbers and a few question

[zchem]

First of all, AWESOME site. Excellent advice/discussions, and I'm very glad to be a member.

Brand new pool just finished construction with RiverRok plaster about 5 weeks ago. I allowed the builder to use trichlor pucks in the auto-dispenser for a short time until I measured CYA to about 50-60 ppm. Then I shut down the dispenser and am no longer using pucks, only bleach. I'm measureing pH and FC daily while monitoring everything else a couple times per week. As expected, I've been adding acid every day as the plaster cures, but noticing a little less demand. I recently added borax (acid first) to get to a calculated level of 30 ppm (about the only main thing my test wont test for). Note that I am in Texas with 100+ temps. Here are my most recent numbers:

FC - 3.0
TC - 3.0
pH - 7.8 (added some acid after test)
TA - 110
CH - 140
CYA - 55

So far, using the levels and advice from this forum, my water is gorgeous clear sparkling blue, and I really want to keep it that way!

Questions:

I have pucks to use when I go out of town. I assume this will result in CYA levels getting too high, so I suppose I'll have to drain and refill some water if/when this happens (week long trip coming up in a few weeks)?

Since this is a new pool/plaster job, should I wait longer before trying to adjust anything else (e.g. CH)?

Thanks again for a great site!

 

[Optica]

Re: New Pool, New TFP member, posting numbers and a few ques

You could try Cal-Hypo tablets instead of Tri-Chlor tabs. That way you would not increase CYA but would increase CH slightly as you need bump up your CH anyway.

 

[Butterfly]

Re: New Pool, New TFP member, posting numbers and a few ques

Welcome to the forum

Your FC is too low. It should be between 4 and 9 and never below 4. Don't want to lose that sparkle!

Since your pool is more than a month old, I suggest you go ahead and raise your CH to about 250 for now.

While on vacation, do you have someone that can come over a couple times - maybe every other day or so - and add bleach and check on things for you?

 

[duraleigh]

Re: New Pool, New TFP member, posting numbers and a few ques

Butterfly meant 4-6ppm (not 9ppm) but your FC is just a tad low. Do not use Cal-hypo tablets.....they are not a viable option.

Your CYA increase will not be a problem simply because you know it CAN be a problem. If your CYA increases to 60ppm or so when you get back, all you need to do is drain about 15% of your water getting it right back down to around 50ppm.

Keep your pH in check (often) and increase your CH a little (just once) and you are good to go.

 

[Butterfly]

Re: New Pool, New TFP member, posting numbers and a few ques

Butterfly meant 4-6ppm (not 9ppm) but your FC is just a tad low.

Hi Dave. Actually, I did mean FC 4 to 9ppm. I got this wider spread from PoolCalculator.Com.
Rather than give folks the more narrow range found in the Chlorine/CYA chart in Pool School, I like to give them enough comfort/info up front that they can safely and easily maintain their target level

Do not use Cal-hypo tablets.....they are not a viable option.

Yep, totally agree. Also, Cal-hypo also does not play well with other forms of chlorine.

 

[zchem]

Re: New Pool, New TFP member, posting numbers and a few ques

Great, thanks for the replies.
So, Butterfly, measuring a FC level of 9 ppm, is it still ok for my family to swim?

 

[zchem]

Re: New Pool, New TFP member, posting numbers and a few ques

Forgot to ask... since the plaster is still curing and releasing some Ca into the water, does that affect how much calcium chloride I add to raise the CH?

 

[duraleigh]

Re: New Pool, New TFP member, posting numbers and a few ques

So, Butterfly, measuring a FC level of 9 ppm, is it still ok for my family to swim?

Absolutely. I forgot about the wider range pool calculator gives. In any event, 9ppm ( and even somewhat higher) is perfectly safe.

Don't overthink the CH. The precise number is not critical. Simply maintain CH around 250-400.

 

[zchem]

Re: New Pool, New TFP member, posting numbers and a few ques

So, Butterfly, measuring a FC level of 9 ppm, is it still ok for my family to swim?

Absolutely. I forgot about the wider range pool calculator gives. In any event, 9ppm ( and even somewhat higher) is perfectly safe.

Don't overthink the CH. The precise number is not critical. Simply maintain CH around 250-400.

Ok, thanks for the reply...

One more question: my FAS-DPD test only goes to 5 ppm without dilution. In order to test up to 10 ppm, I have to dilute the sample with tap water (4.5 mL with 4.5 mL)? Is this the best way to test for 5-10 ppm FC?

 

[Butterfly]

Re: New Pool, New TFP member, posting numbers and a few ques

Great, thanks for the replies.
So, Butterfly, measuring a FC level of 9 ppm, is it still ok for my family to swim?

As Dave said, yes, it is perfectly fine for your family to swim in!

Forgot to ask... since the plaster is still curing and releasing some Ca into the water, does that affect how much calcium chloride I add to raise the CH?

Since it is still curing, I suggest you raise CH to the lower end of 250 for now.

 

[Butterfly]

Re: New Pool, New TFP member, posting numbers and a few ques

One more question: my FAS-DPD test only goes to 5 ppm without dilution. In order to test up to 10 ppm, I have to dilute the sample with tap water (4.5 mL with 4.5 mL)? Is this the best way to test for 5-10 ppm FC?

The FAS/DPD tests up to 50 ppm.

The OTO (yellow drop test) tests up to 5 ppm.

The best way to test for FC/CC is to use the FAS/DPD test. Which test kit do you have?

 

[zchem]

Re: New Pool, New TFP member, posting numbers and a few ques

The OTO (yellow drop test) tests up to 5 ppm.

The best way to test for FC/CC is to use the FAS/DPD test. Which test kit do you have?

I meant to say DPD test (not the FAS-DPD). I have the Leslie's (Taylor) 81-330, which uses the three reagents (buffer, DPD for FC, then third reagent for TC) and color block.

 

[anonapersona]

Re: New Pool, New TFP member, posting numbers and a few ques

I always keep some cal-hypo on hand, it stores well. In the big 90 lb bucket from Leslie's it is close to the price of bleach per ppm of FC and that makes the calcium part essentially free. Good to use when you have the ability or need for more calcium. I pour it in the shallow end then use the Wall Whale to mix it well.

For a week's vacation I push the FC up to shock level and then put just a few trichlor pucks in the feeder, about 1 per day. Put the chlorinator on a low setting and I'm pretty sure that the pool is fine untended for the next 4 days. I do have someone come over late in the week. They need to check the skimmers and the water level and depending on who it is, they may test and add a jug of bleach (if they stay to swim) or maybe I ask them to just add a jug and figure that is enough.

I am actually more worried about the skimmers getting full and sucking air or the water level getting too low than I am about FC getting low or even the CYA getting high -- those I can handle on return. Burned up pump is much harder to deal with.

I usually try to fish the leftover trichlor tablets out of the Rainbow 320, not an easy task. Sometimes I just let them stay. Interesting to see how long the pH effect lasts. You do want to be aware of the effect on TA and if your TA is very low consider whether you want to boost it just a bit for that time. I don't worry when TA is 80 - 90 or more but if it is at 70 when I switch to tablets, I do think about the length of the trip and the possibility of TA falling lower if lots of rain is expected. Pretty rare for TA to actually be that low for me. Actually only happened after a long trip with lots of tablets used. Just a heads up that with a vacation coming up you don't want to be aggressively trying to reduce TA to control pH only to find that the effort was wasted.