Starting resurfaced pool

[Kidney]

Things are looking better!

Yesterday morning pool was looking bluer after adding the bleach but TC was low, I added a bit less than 2lb of baking soda to raise my TA then several hours after that after noon added a dose of muriatic acid to lower my pH. In the evening around 9pm, once water had had plenty of time to recirculate with pH and TA in range, I added 2/3 of a pound of dichlor based on my understanding of what is needed for the 14k gallons I have without exceeding the upper limit of what the NPC recommends. 4 hours later, TC had raised a little (0.5) nowhere near the 3ppm I was expecting. Around 1am, I added the same quantity of dichlor again.

This morning around 8:45am:
FC 1.6
CC 0.4
pH 7.3
TA 80
CH 160
Water temp 80
SI -0.45

Tonight I will add another dose of dichlor 55% AC and so on every evening until I run out of the six 1lb bags I got. That should add a tad more than 30ppm of CYA total (if I calculated that right), which should show on the K2006C CYA test. Hopefully by then I get a feeling of how FC/CC last under current conditions, can add some more CYA and switch over to using bleach.

Questions:
1/ Once CYA rises, should I cease measuring TA and measure Carbonate Alkalinity instead?
2/ How much salt/sodium can I expect to add to the pool by recurrently topping off with bleach?
3/ I have a DE filter and a heater for the hot tub that are both parts of the pool system: I hope dichlor then bleach are ok for use with those, are they?

[BigDave]

A) 7lbs of dichlor should get you right up to 30.

1) Does it matter? CYA will affect measured TA consistently. You will raise it if your pH is unstable - you will determine the best level. The CYA component factors out when comparing new TA reading to old, why bother doing the calculation?
2) A little, maybe 10ppm salt in a jug of bleach.
3) Just fine - no differrent than any other source of chlorine.

[Kidney]

Thank you BigDave!

A) Good! At least my calculations are not off ;-)

1) I see. It's just that the NPC asks for CA not TA to be measured once the pool is started and recommends CA be kept between 80 and 120ppm.

2) Does that little amount of salt translate into huge amounts over several years? I'm not really sure how to calculate this and don't know if I should bother but I sure wouldn't want to see metals rusting around the pool... I just hope this isn't a bad tradeoff vs using Trichlor and having CYA steadily increasing over the years which in my case and in the past led to algae (as I assume chlorine levels couldn't keep up with high CYA) and to having to empty the pool at least partially. CYA does not evaporate right?

3) Great. I was wondering as I saw the post about running pools at high pH where dichlor is a source of chlorine never to be used. However I don't think I could easily run my pool at high pH since I have a heater that would perhaps (?) suffer from this.

[PoolDoc]

+ All forms of chlorine add salt, because -OCl (free chlorine) => O2^ + -Cl (salt) . Bleach adds somewhat more, because it contains free salt, in addition to the chlorine.

+ CYA does not evaporate. It is readily biodegraded however, whenever 'slime' (algae + bacteria) layers form in the pool.

+ Heaters are one place where the SI index actually does matter. You can use the LSI calculator, here, but remember you must use the water temperature at the INSIDE SURFACE of the heat exchanger. A reasonable estimate is the heater effluent temp + 20 degrees F.

So, if your pool is 75 and the heater effluent is 85, you'd use 105 as the calculation temp. Taking your reported figures, and assuming a TDS of 500 ppm for a freshly filled pool, your POOL has an LSI of -0.26, but your HEATER would have an LSI of 0.1

[Kidney]

Great info PoolDoc!

2) So with all forms of chlorine adding some salt, no need to worry about rust with bleach then ;-) Re CYA biodegrading, I will keep an eye on it anyway and can add as needed. I just don't expect much loss if maintenance of FC level prevents slime.

3) To evaluate the LSI, I have so far used the watergram wheel in the K2006C kit *and* the water temp provided on the display of my Hayward H400FDN heater. I wonder what this temp really corresponds to now that you're mentioning this. I believe it is really close to what the temp is in the pool. Based on your explanation, I understand I only need to adjust the temp reading at the heater by +20 when it runs. I will take a look at the LSI calculator.

Re vacation/away time, I found a procedure about this on the Super Simple Startup Recipe page that does use polyquat. I guess this is what you were referring to. Interesting.

Re protozoan cryptosporidium, I found the procedure apparently from the CDC to fight it at this link: http://www.floridahealth.gov/healthy...ponse_reco.pdf

[PoolDoc]

2) You could take it that way, but it's not what I meant.

3) The LSI value that matters, with respect to your heater, is the LSI of the water 1/32" of an inch away from the interior of your heat exchanger pipes . . . and yes, THAT water will be at a higher temp than your pool water.

4) I'm working a vacation page. Polyquat can be a helpful tool with any approach. Basically, your options (which can be combined) are: use a feeder, use a floater, use an SWCG, use polyquat, maintain borates > 60 ppm, maintain phosphates < 100 ppB, follow HiC2 (high CYA + high chlorine) and raise FC > 30 ppm before leaving, cover your pool.

The crypto guideline has been updated since I last saw it. It was amusing to see how closely it aligns with what I tell guards: "It's not the nice t##d that will make everyone sick; it's the disappearing brown cloud!". Then, I usually 'share' with them information about a black bear's first meal after hibernation.

[Kidney]

PoolDoc:

2) Not sure I understood you. Do I need to worry about the salt that bleach adds and/or disappearing CYA?

4) I'll be glad to read your vacation page. Hope I don't miss it especially since I'd like to learn about borates and phosphates. That Phosfree product at Leslie's really has me wondering what benefit it could have....

5) I have CC and its level could rise. How do I get rid of it? increase TC 3 to 4 times my FC reading or in some other way?

If there are more current guidelines re crypto, it would be great to know even if there are no bears in sight here 8-D