"pre-opened" my pool last month. that is I got the pump going, did an initial scrub and vacuum and added chlorine. Haven't done much since. With cool weather water stayed clear. today I vacuumed very good and removed all leaves and debris. Water wad clear and no signs of algae. I then added about six pounds of Sodium Dichloro-S-Triazinetrione and in about ten minute the entire pool was pea green. It is supposed to go the other way. Put chlorine in green water and it turns clear. Why did this happen? Not sure what to do. I have always used calcium hypochlorite before. Does Sodium Dichloro-S-Triazinetrione act differently?
Chlorine turns water green
- Thread starter dumpsterdan
- Start date
Welcome to the forum. :lol: This is an ongoing puzzle, I think, in that my pool has done the same thing the last three Springs. It is not the tri-chlor but rather the chlorine in the trichlor. All I use is liquid chlorine.
That said, when pool water reacts to chlorine like that the first suspect is iron in the pool water. Can you tell me if you have ever tested your iron content?
That said, when pool water reacts to chlorine like that the first suspect is iron in the pool water. Can you tell me if you have ever tested your iron content?
Welcome to tfp, dumpsterdan 
My guess would be metals, but it sounds like you have never had the problem before? What is your fill source?
My guess would be metals, but it sounds like you have never had the problem before? What is your fill source?
I have not tested for metals. Fill source is municipal water system. Water quality coming if very good with extremely low metals and ph just where it should be. My pool is around 30,000 gallon of a little more. I had ordered a pool start-up "kit" which included 50 lbs granular chlorine and 24 bags of shock (12 non-chlorine). I scattered a couple of one pound bags of chlorine shock last night before i started the clean up and vacuuming this morning. After cleaning I added about five pounds of granular broadcast. I intended to over-chlorinate since we probably won't be in the pool for at least three more weeks. That is when it turned green. Started reading labels and discovered shock is cal-hypo and the bucket of granular is Sodium Dichloro-S-Triazinetrione. Had no clue so registered for this forum.
Your best friend will be a good test kit. Take a look at the link in my sig, my favorite is the tf100, best bang for the buck. Dichlor adds cya to your pool which can be overdone. Take a look at http://www.troublefreepool.com/pool-school/types_chlorine_pool for a discussion of chlorine sources.
ddan, it is not clear to me what product you added that turned the pool green. Can you tell me?
The information for the product which I added just before it turned greeen is below from the label.
In The Swim granular chlorine
Powerful 56% available stabilized chlorine.
99% Sodium Dichloro-S-Triazinetrione.
Granular chlorine must be pre-dissolved in a bucket before adding to the pool.
Fast dissolving – pH balanced.
Approximate use per day – 2oz per 10,000 gallons.
In The Swim granular chlorine
Powerful 56% available stabilized chlorine.
99% Sodium Dichloro-S-Triazinetrione.
Granular chlorine must be pre-dissolved in a bucket before adding to the pool.
Fast dissolving – pH balanced.
Approximate use per day – 2oz per 10,000 gallons.
BTW - Thanks for all the welcoming comments. Forums are great places to share information. I use them for my vehicles and other products like the iphone. Amazing how much information you can learn from hundreds of folks with experience. Thanks for allowing me to be here and also for the quick responses. I'll toast to that. 
Just ran a quick test. Results:
ph 6.5
FC 10 mg/L
TA 35-40 mg/L
CYA less than 25 ppm
ph 6.5
FC 10 mg/L
TA 35-40 mg/L
CYA less than 25 ppm
Hopefully you know this already 
but you need to get the PH and TA up as soon as possible. Long periods of low PH can damage the pool. I suggest using borax (or soda ash if that is simpler) to raise the PH to at least 7.2. After doing that test the TA again and see if it still needs adjusting as well.
but you need to get the PH and TA up as soon as possible. Long periods of low PH can damage the pool. I suggest using borax (or soda ash if that is simpler) to raise the PH to at least 7.2. After doing that test the TA again and see if it still needs adjusting as well.Thanks. I have been working on the ph today. Will try to stabilize it at around 7.2. This morning pool was crystal clear but still green. Like looking through the green glass in an old coke bottle. The "kit" i purchased came with a quart of "stain remover". No chemical information on the label but said it would help with metal related stains on the pool surface or in the water. I added it to the pool about 9:00 and by 10:00 we were sparkling clean and clear with no color. Now I will get the chemistry balanced and be ready for the season.