To drain or not to drain

mybluepool

Active member
Jun 11, 2010
39
Hello,
Tested levels yesterday (w/my new mac daddy kit) and CYA is around 70-85. I am planning on shocking since I have visible algae. My pool is situated East to West so it gets full sun pretty much all day and temps stay in the 100+ here. Should I just precede with using the 10 gallons of 10% bleach (my FC is darn near 0) to start the process or should I drain some water off. It doesnt seem to make a difference on amount of bleach, using the pool calculator.
Appreciate feedback.
 

anonapersona

TFP Expert
LifeTime Supporter
Nov 5, 2008
2,598
What is the rest of test data?

It will make a difference since your goal will be lower at lower CYA. if CYA is now 80 and you lower to 40, shock FC is half of prior level. May reduce CH levels as well, depending on test data vs fill water.

Gotta go, got tickets to Dave Mathews tonight!
 

mybluepool

Active member
Jun 11, 2010
39
Well, pool school says "If you have a SWG or very high levels of direct sunlight, CYA is typically kept between 70 and 80". So if I drain down to 40 then my FC shock level is 16 vs. 30 but then will I just be using more chlorine to maintain because my CYA is lower. Will I need to add more CYA after shocking, I'm confused now.
TA 140
pH 7.8
FC 2
CH 330
CYA 70-85
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
There is no need to drain...CYA of 80 is still manageble...just make sure you keep your FC at shock level.
 

mybluepool

Active member
Jun 11, 2010
39
zea3 said:
Do you have an SWG? It is not listed in your signature.
No I have "very high levels of direct sunlight". I stated in the first post the orientation of my pool.
I am going to start the shock process tonight, 10 gallons of 10% bleach.
Here goes!
 

anonapersona

TFP Expert
LifeTime Supporter
Nov 5, 2008
2,598
It is your call, you can make an informed choice. if dbman says 80 is OK, well there you go. Run with it. I'd chose differently but that is just me.
 

Shane1

LifeTime Supporter
Apr 29, 2010
621
Buckeye, AZ 85326
I dont think there is any reason you should replace water. My CYA is in the same ballpark as yours and I still go through about half a gallon of 10% a day. Thats keeping a target of 8ppm FC, but at the end of the day its down to about 3ppm. My pool is east to west as well with no shade until about 5:30pm. What I do find odd is that my pool is 1/3 the size of yours and we are using the same filter set up. I would think your pool would need the next size up.
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
anonapersona said:
It is your call, you can make an informed choice. if dbman says 80 is OK, well there you go. Run with it. I'd chose differently but that is just me.
I'd normally say CYA of 80 for a non-swg is too high, but given the heavy sun exposure, no need to bring the CYA level down, just to bring it back up again. I'm thinking the cost of additional chlorine needed to maintain shock level at CYA of 80 will be a lot less vs draining/refilling +15,000 gals and then bringing CYA back up, if needed. That's just my opinion though and I have not done any cost benefit analysis...just instinct :)
 

mybluepool

Active member
Jun 11, 2010
39
I was also weighing the cost of draining and filling vs. chem costs,. water is cheap here and it may cost ~ $50-75 to replace, but the chemicals will cost as much and then I will need to use more chlorine post draining to maintain even 5ppm FC, right? (because of solar breakdown)
anyone know where i can get bulk bleach at 10% strength? one gallon jugs get used so fast and are so wasteful. I am really considering a swg. haha the hubs will surely laugh at that one.
@shane1 not sure about the filter, I was told we have a commercial pump though. oh and dear god I cant imagine cleaning the "next size up" my record so far is 2.5 hrs.
 

Shane1

LifeTime Supporter
Apr 29, 2010
621
Buckeye, AZ 85326
I found a place on Grand & 67th ave that would sell me 12.5% in 5 gallon buckets for 10 bucks. It was a back alley kind of deal and kind of a pain. The price was right but the logistics sucked. I dont remember the name of the place.
I would think for a pool your size that is never going to be closed a SWG would be the way to go. I will get one soon hopefully.
Another thought: Since you dont have a problem paying for the water you might want to consider doing it the old fashion Arizona way, with floaters and pucks then drain some water out when your CYA gets out of control. I know thats going against the grain here but your pool is huge. Feeding that monster bleach would get old quick.
Maybe one of the builders/experts will chime in about your filter size.
 

mybluepool

Active member
Jun 11, 2010
39
Shane1 said:
I found a place on Grand & 67th ave that would sell me 12.5% in 5 gallon buckets for 10 bucks. It was a back alley kind of deal and kind of a pain. The price was right but the logistics sucked. I dont remember the name of the place.
I would think for a pool your size that is never going to be closed a SWG would be the way to go. I will get one soon hopefully.
Another thought: Since you dont have a problem paying for the water you might want to consider doing it the old fashion Arizona way, with floaters and pucks then drain some water out when your CYA gets out of control. I know thats going against the grain here but your pool is huge. Feeding that monster bleach would get old quick.
Maybe one of the builders/experts will chime in about your filter size.


LOL that is a 'back alley' deal but i may just check it out. I think that the ole' arizona way may be what we do, cause the H2O is cheap here, but the chlorine ain't. :grrrr:
so far my FC is 30 and I am 11 gallons in. thats $40 so far, once I am blue again I have some serious decisions to make.
 

mybluepool

Active member
Jun 11, 2010
39
Update on shock process (24 hrs in)
FC 41
pH 7.8
Water is hazy, cloudy light green
running filter 24/7
approx 18 gallons 10% chlorine thus far ($64)....blue pool is not priceless at this point.
need pep talk a.s.a.p
Fawn
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
Don't worry about PH at such a high FC...it will read falsely high. Other than that keep the FC level high with the pump running 24/7 and check your PSI frequently to ensure you do not need to clean the filter. Your doing good :goodjob:
 

mybluepool

Active member
Jun 11, 2010
39
Ok update 48 hrs shocking
FC 31.5
Pool color: blue but cloudy still, although can see deep end for first time in ~60 days
23 gallons of chlorine 10% used ($80)
just added 1 gallon ($83.50)......going to store to get more chlorine
pump running 24/7
looking smugly at husband with blue pool in background over breakfast.....priceless
 

mybluepool

Active member
Jun 11, 2010
39
update 72 hrs
30 gallons in ($105)
FC 30
pump still running, PSI is holding at post cleaning level, cleaned filter two weeks ago.
pool color is blue and can actually see the bottom, adjusted polaris jets...some not turning. first time doing this in at least 3 months.
bought 6 gallons yesterday...used them all! going back to store to buy more, what are your thoughts on cal-hypo 65%, seems to raise CH only minor amt. mine was 330 one week ago.
planning on checking FC loss overnight tonight, hoping shock process will be over tomorrow.
 

mybluepool

Active member
Jun 11, 2010
39
yes, but that doesnt really answer my question. using liquid chlorine is going to take a lot and get expensive fast. 2 gallons is $7, I will be using at least 1 to 1.5 gallons a day or more to maintain 8-9ppm FC. thats $100+ a month, just chlorine. not including acid and electricity to run the filter. not only the cost but storing and pouring everyday is not practical.
i need suggestions??? anybody
 

dmanb2b

TFP Expert
LifeTime Supporter
Apr 4, 2009
3,734
NY
Using other forms of chlorine will not be any cheaper. As for convenience, as I've mentioned before, given the size of you pool, I would seriously consider a SWG. Yes it's a high $ cash outlay upfront, but as you've said will save you $100/mo in liquid chlorine. The avg SWG can last 3-7 years. Bottom line, spending $100-$200 a month on a $30K gal pool is not unreasonable.

Let's say say you purchase a SWG, I'll use $2,000 as your investment cost (SWG and salt) and assume you have your pool open 6 months per year and a conservative 3 year life, your looking at about $110/mo if you spread that cost over the useful life. Not having to lug jugs...priceless :goodjob: