Do the Member's Mark Tabs have stabiizer?

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
43,238
Tucson, AZ
And your pool in the past was not properly sanitized; there is a reason you ended up on TFP ;)
Safe sanitized water vs. save some $ on chlorine, but not have sanitized water and also fight algae ... choice is yours.

There are a few cal-hypo tablets without CYA, but they add CH (which you do not want) and they turn into a mushy mess.

Look for a pool store that sells bulk liquid chlorine in refillable jugs. Around here HASA is the distributor to some of the NON-chain pool stores.
I think I pay about $3.99/gal of 12.5% and the 12th is free.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
29,646
Laughlin, NV
I know that some members in your area get bulk liquid chlorine in refillable containers.
Take a look at Best Places to Buy Liquid Chlorine

There is cal hypo, but that will push your CH up. You do not have any test results in your shared Poolmath log so I do not know if you have room to use cal hypo. What is the CH of your fill water (though I suspect rain primarily fills your pool).
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
43,238
Tucson, AZ
Some math:
LPS sells 100 pound bucket of trichlor tablets for $255 ... that is $2.55 / pound and in our 18k pools a pound adds 6.1ppm of FC ... so $0.42 / 1ppm of FC
1 gallon of 12.5% bleach is $3.99 ... that adds 6.9ppm of FC ... so $0.58 / 1ppm of FC
EDIT: Although with the 12th gallon free, the price ends up $3.66 / gallon or $0.53 / 1ppm of FC

So the tablets are about 25% cheaper from a FC standpoint. But with the bleach you are not having to counter the acidic tabets by raising the TA and pH and you are not building up the CYA and having to pay for water replacement. And as I mentioned before, now your water is actually properly sanitized.

EDIT2: With a typical FC loss of 3ppm per day, you would need 1 tablet to completely dissolve everyday ... is that what you observed? If not, then the FC was likely too low.
 
Last edited:

Rick T

Well-known member
Apr 28, 2019
106
Houston, TX
I just ran all my tests. here's what I found:
CH: 400
TA: 99
CYA: 80
FC: 11 (I added liquid chlorine a few hours ago)
CC: .5 (it took only 1 drop to go back to clear)
ph: 7.5
 

IceShadow

Gold Supporter
TFP Guide
Jun 8, 2019
2,177
Milwaukee, WI
Have you tried testing your FC levels after sunset at night and then before sun hits the pool the following morning, just to make sure you don't have any organics eating your FC? (We call that OCLT or Overnight Chlorine Loss Test.)
 

Rick T

Well-known member
Apr 28, 2019
106
Houston, TX
I will try testing it tonight. I had my water tested last month at Leslie's pools. All I remember is that they said my phosphate levels were high. I bought Orenda Technologies PR-10000 Phosphate Remover - 1 qt online last week. It hasn't gotten here yet.
 

IceShadow

Gold Supporter
TFP Guide
Jun 8, 2019
2,177
Milwaukee, WI
If you manage your chlorine levels correctly the way the site here advocates, your phosphate levels will be irrelevant. It's algae food but if it can't live, it can't eat!
 

Rick T

Well-known member
Apr 28, 2019
106
Houston, TX
I copied this from another thread I'm on:

I just came back from Home Depot. They have a 3-gallon case of liquid pool chlorine rated at 10% for $9.98. If you buy 4 or more cases then they drop $1/case. Comes to $3.24/case with sales tax. That's the lowest I've seen so far. Walmart's 10% chlorine came out to $3.94 with tax. Multiply that times the 12 bottles I bought at Home Depot and I saved $8.40. Helps a little.
 

mguzzy

Gold Supporter
Jul 8, 2015
1,800
OV, CA
At $4/gal including tax from Walmart is there a cheaper solution for liquid chlorine? At that rate I'm over $100/month in chlorine alone. My chlorine tablets used to cost about $200-300/year. Is there a non-stabilized (no CYA) chlorine tablet available? I still have a 3/4 large bucket full of tablets but didn't want to use them for fear of bringing my CYA back up.
Have you considered retrofitting your pool with an SWG?
 
Last edited:

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
29,646
Laughlin, NV
In Houston, your environment will eat up your flagstone.

The low level of salinity in a pool using a SWCG will have no additional effect. Poorly managed pH will have an effect.
 

mguzzy

Gold Supporter
Jul 8, 2015
1,800
OV, CA
You have already spent enough money in gas going back and forth from Wallymart and Home Despot to pay for a SWG.. just a rough estimate! ;) I like my SWG for the automation and how much easier it makes managing my pool Chem. You will find lots of testimonials from people that have SWG's here. It seemed like you might be a good fit for one.
I have found a lot of people that make statements like that don't have a true concept of how much salt is in a pool with an SWG. That probably came from someone the builder knew that had flagstone landscaping on a property near the ocean and flagstone is probably not suited to that environment. A salt pool is around 3000 to 4000 ppm, the ocean is about 34,000 ppm, tears are about 7000 ppm... so by that logic don't cry on your flagstone.
 
Last edited:

red-beard

Gold Supporter
May 27, 2019
93
Houston, TX
I'm buying 10% Chlorine from Home Depot. If you buy the 3 gallon box and buy 4 boxes at a time, it is about $3/gallon. There is another thread on Chlorine sources and there is supposed to be a place in Kline/Tomball that sells 12.5% for about $1.80/gallon (you supply the container).
 

Rick T

Well-known member
Apr 28, 2019
106
Houston, TX
I'm buying 10% Chlorine from Home Depot. If you buy the 3 gallon box and buy 4 boxes at a time, it is about $3/gallon. There is another thread on Chlorine sources and there is supposed to be a place in Kline/Tomball that sells 12.5% for about $1.80/gallon (you supply the container).
If you find that one out let me know. I'm down south in Missouri City but might be worth stopping by if I'm up that far.