Long term use of Trichlor

BenTaylor

Member
Apr 1, 2018
19
Grapevine, TX
Long time reader, infrequent poster. I have a problem, I've been using tablets for the last three years. This spring, I'm realizing the error in my ways. I got a pool store test a couple weeks ago and my CYA was up over 100 ppm. My water is crystal clear, but I'm having problems with algae with growing on the sides of the pool. I suspect the CYA level is too high and that's inactivating the chlorine that's coming from tabs. I've drained some water from the pool in an attempt to lower the CYA level, but haven't rechecked the levels yet.

My go forward plan is as follows:
1. I'm ordering a new test kit.
2. No more tabs and only liquid chlorine.
3. What's next?

Thanks,
Ben
Grapevine, TX
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
1,647
Prosper, TX (DFW)
Hey Ben - Sounds like you are on the right track. In addition to what you have listed, you should read up in pool school, and prepare to follow the SLAM process to fully get rid of your algae. I would recommend walmart for their pool essentials liquid chlorine in our area.

 
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dawei213

Member
Apr 26, 2013
21
Philadelphia, PA
While waiting on the kit, stock up on liquid chlorine. You have algae and will need to slam after you do a partial refill to lower your CYA.
Just jumping onto OP's thread but figure this question maybe helpful as well. If it's hard to find liquid chlorine due to not being able to go out (stay at home order) or unavailability, are there other alternatives other than the tablets?

I've been using liquid chlorine for the past 6 years and it's been great. Never ever used tablets so I'm hesitant to start but may not have too much of a choice.
 

Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
1,604
Rancho Cucamonga, CA
Just jumping onto OP's thread but figure this question maybe helpful as well. If it's hard to find liquid chlorine due to not being able to go out (stay at home order) or unavailability, are there other alternatives other than the tablets?

I've been using liquid chlorine for the past 6 years and it's been great. Never ever used tablets so I'm hesitant to start but may not have too much of a choice.
It depends on your your test results for CYA and CH. Your options are trichlor/dichlor (add CYA) and/or cal-hypo (add calcium). Pick your poison, so to speak. If your chemistry allows for increases of either, they are viable options. You can use Pool Math to estimate how much CYA or calcium each form will add by weight.
 

Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
1,604
Rancho Cucamonga, CA
At first, until you get to know your pool, you'll test frequently. As time passes, those daily tests (mostly for pH and FC/CC) will turn into two or three times per week. You will need to dose chlorine daily. You don't ever want your FC to fall below the minimum for you CYA level.
 

BenTaylor

Member
Apr 1, 2018
19
Grapevine, TX
My TF-100 kit came last night and I just tested my water and uploaded to Pool Math.
FC/TC = both .5ppm
PH = 7.8
TA = 100
Calcium Hardness = 525
CYA = 90

I’m off to buy chlorine and drain the pool some more. What’s next?
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
12,643
Houston, Texas
Use muriatic acid to drop the pH to 7.2 before you start the slam. Once the slam starts pH will read high, and will drop off to normal range as the FC level drops.

Do you naturally have hard water in your area?
 

BenTaylor

Member
Apr 1, 2018
19
Grapevine, TX
I drained 2/3 of the pool water this morning and I'm almost back to restarting the pump, which should happen in the next few hours. How long should I run the pump before determining my new numbers? Can I start SLAMing the pool tonight?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
33,062
Laughlin, NV
Before testing CYA level run the pump for several hours. Better is overnight.
Add liquid chlorine to reach SLAM level FC based on your expected CYA level.
Test the CYA tomorrow. .
 
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BenTaylor

Member
Apr 1, 2018
19
Grapevine, TX
I ran the pump over night and checked the chemicals the first thing this morning:
FC/TC = both .5ppm
PH = 7.8
TA = 120
Calcium Hardness = 375
CYA = 40-50

I added 1 qt. of 31.45% muratic acid to lower the PH and about 45 minutes later I added 2.5 gallons of 10% liquid chlorine.

I also checked my tap water this morning and my CH for that 250.

When should I check the chlorine levels next.

The water is completely clear.

Thanks,
Ben
 

BenTaylor

Member
Apr 1, 2018
19
Grapevine, TX
Keep the pump running all night as well?
Regarding organics, I've got cedar trees around in the yard and around the pool that drop stuff into the water. I'm doing my best to keep this stuff out of the water, but will this dead stuff also consume the chlorine?