New guy Questions

[waterbear]

I've been lurking around for a while now gleaning as much info as possible and I have a couple of questions that I can't seem to get out of my searches.
Using exclusively BBB method because I like it.

New Pool: 2 weeks with water in it. I've done all the start-up stuff myself with help from info on this site. Pool guy is a pool builder not a maintenance type. Not much help!
20X40 25000 gals IG vinyl
Numbers
TC = 3
Ph = 7.6
Alk = 70
CYA = 20-30 let's say 25
Ch = ?
Temp = 87

The cheapo Aqua-chem "Professional Test kit" just doesn't cut it for the testing stuff but it's getting me by right now.
Ok now for my questions.
(1) The first part of the Ch test turns blue in 2 drops to indicate hardness but the second part to clear only takes 2 drops to indicate a ch of 100 I think. Is this ok or do I need to do something with this number? Vinyl pool, no heater, no swg. I noticed that this problem has been hashed over thoroughly and a search of "Aqua chem" gave me the answer to this question which is my kit won't accurately tell me.
There are some issues with this test in the aquachem kit. when you add the indicator the sample should turn pinkish when there is hardness present. you then add the titrant drops and count them until the sample turns blue. If the sample is turning clear pale yellow when you add the indicator try adding more indicator until it turns pink (or stays blue...means no hardness in the water) and then titrating.
(2) I have been working on my alk # and have it up to 70 and it is holding ph well. Should I try to bump it up a little more just to get it "in range" even though ph is remaining stable.

Thanks in advance for the help and the great info on this forum!!!

Hope this is helpful.

[chemistrydropout]

Thanks for the input/help/encouragement. I am currently holding ph very well with my alkalinity #'s. I am adding 3 quarts of 6% bleach every day to maintain a chlorine level of 3. I have a fairly heavy swimmer load with one small child daily combined with 100 degree days and lots of sun. I feel that this is to be expected. The 2 days that no one swam I ended the day with chlorine levels at 3 one day and between 2 and 3 the other day. What do the experts think of my cya???

[duraleigh]

Chem,

You don't say how much ppm you lost during the day...only the ending ppm. I assume to be about 2-3ppm. That's not bad. I've been losing about 4ppm with a CYA of 30 so I recently upped my CYA to 50, hoping to slow my loss to around 2ppm.

The CYA level is ultimately your call. You can always add more but it's difficult to reduce.

I still see no reason to maintain your Alk outside recommended levels (80-120) but then, if it ain't broke.....

[chemistrydropout]

I am losing a little less than 2 ppm on hot days with swimmer load. I am thinking that is to be expected. Am I right?

[waste]

CDO - welcome to the forum (very welcome actually as you've read and researched before posting)! It's been hinted at in the other responses but , If it ain't broke, don't try to fix it! One of the tenants here is to keep things simple by adding only what you need to to correct a problem - this also has the advantage of saving you $. I, personally think that cya = 25 is the perfect ballance between keeping a chlorine residual vs the reduced killing power, however I know that Watermom keeps her's higher and Duraliegh has just upped his, and they know what they're doing.
Congrats on a great post, you've gotten nothing but all-stars to respond (myself excluded ) I like the cut of your jib!!

[chemistrydropout]

Just an update here. My chlorine levels started bouncing around a little these last few days. I was going from between 4 and 5 ppms down to less than 1 ppm in the evenings. That's a loss of 3 to 4 ppms a day. I was not pleased with the loss (which could be from a large swimmer load or these over 100 degree temps we've been having) so I added another pound of cya. I have not tested the cya yet because it has only been in the water for less than 4 days now. It seems to be working out much better though. The last two days I am back down to about 2 ppm chlorine loss.

[waterbear]

Just an update here. My chlorine levels started bouncing around a little these last few days. I was going from between 4 and 5 ppms down to less than 1 ppm in the evenings. That's a loss of 3 to 4 ppms a day. I was not pleased with the loss (which could be from a large swimmer load or these over 100 degree temps we've been having) so I added another pound of cya. I have not tested the cya yet because it has only been in the water for less than 4 days now. It seems to be working out much better though. The last two days I am back down to about 2 ppm chlorine loss.

With a 25000 gal pool one pound will increase your CYA about 5 ppm. Since you said before that your CYA was about 25 ppm (a bit on the low side given your high temerpatures and a large swimmer load) I would bump it up with a second pound for about a total of 10 ppm increase. This will definitely get you into the desired range of 30-50 ppm. If you are still getting a large chlorine loss then you might want to bump it up a bit more and run at slightly higher chlorine levels and shock levels.