New to TFP and need help with Algae

[zmurphy1972]

Hello everyone, I really need some help! This is our 4th year with our Intex XTR 20'x48" pool. After $50 to $100 weekly trips to Leslie's pools, we switched to TFP method a few months ago. I bought the better TFP test kit, everything has been great and SO easy this year. Until a couple of weeks ago..... We went on vacation for a few days and came home to a slightly green pool. After researching, it appears to be due to low chlorine and a bunch of rain. I cleaned the pool really well, used some Green Out and did my normal water testing. everything was great, nice and clear for 2 weeks. I just did my weekly water testing 2 days ago, things weren't bad, I added recommended chemicals from the Pool Math app.

Today, It looks like we have some mustard algae! My levels should've been right on after testing and adjusting 2 days before, WTF? I freaked out and added 20-30 oz of liquid chlorine, that I had left in a bottle (10%). I went ahead and tested my water afterwards. I'm no chemist and I'm still learning, but the numbers don't seem to be off much. Why am I getting mustard algae and how do I treat to knock it out, using the TFP method?

Current levels are:
CL: 5
BR: 10
pH: 7.8 (Pool Math says to add 4.7 oz Dry Acid)
FC: 5 (Pool Math says add 10 oz liquid chlorine)
CC: .5
TC: 5.5
TA: 70 (Target 70)
CYA: 50 (Target 45)
CH: 275 (Target 300, add 30 oz Calcium Chloride)

 

[JJ_Tex]

Hey Murphy - Sorry you have a green pool. A couple of key points/questions:
- Algae is always caused by low chlorine. Its easy to get caught up in the other metrics, so FC should be your primary focus-
- Make sure you understand the FC/CYA relationship and maintain your FC at the correct level. The chart is below, but the numbers you posted above is below the target FC level, which probably explains the algae.
- What the heck is "Green Out"? It sounds like a pool store potion. Tell us the ingredients and we can figure out what exactly you added to your pool.

So now that you have algae, the way to kill it is the SLAM method. Read this multiple times, and ask questions. Hopefully it isn't too bad and we can clear up your pool in a week or so:

SLAM - Shock Level and Maintain

We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.

www.troublefreepool.com

My FC/CYA chart:

 

[zmurphy1972]

JJ_Tex, TY for the reply! LOL. I misspoke, it was actually Green to Clean https://lesliespool.com/coral-seas-green-to-clean-2-lbs/15975.html

Obviously, I still have a lot to learn. I kinda understand the FC and CYA relationship. My CYA has been running 40-50 most of the summer. With that the Pool Math app says FC should be 5-6. So, if that's low and causing the algae, that does make some sense to me. I am following the SLAM method and will update! TY again!

 

[AUSpool]

Testing is great but you’ve got to understand what happens in between testing too. In your case while on holidays the chlorine dipped bellow minimum and the algae starts to take hold. Your FC was 5ppm after adding 20 - 30oz which means there is still some algae consuming the FC.

And then there’s the green out which appears to be ammonium sulphate. This can act like a flocculant but mostly chlorine will react with it to produce ammonium reducing the effectiveness of you chlorine. I would toss the green out and SLAM.

I would also switch to muratic acid. Dry acid adds sulphate to the pool.

 

[zmurphy1972]

AUSpool, the last 2 weeks, test results said to add dry acid (which was the first time this season). Between the Green to Clean and the Dry Acid, would that have helped the algae grow? I'm out of GtoC and won't buy anymore. I starting slamming yesterday afternoon and my FC is 21 right now. It looks much better this morning. TY for the help!

 

[PoolStored]

Please suspend the use of dry acid. Use muriatic acid to reduce pH. Dry acid adds sulfates...no bueno for el poolo.

Recommended Pool Chemicals

Which should I buy? TFP's recommended pool chemicals are cheap, easy, and won't unbalance your pool water.

www.troublefreepool.com

Non-Recommended Pool Chemicals

These pool chemicals should not be added to your pool. Save your money and frustration and avoid these chemicals!

www.troublefreepool.com

 

[JJ_Tex]

AUSpool, the last 2 weeks, test results said to add dry acid (which was the first time this season). Between the Green to Clean and the Dry Acid, would that have helped the algae grow? I'm out of GtoC and won't buy anymore. I starting slamming yesterday afternoon and my FC is 21 right now. It looks much better this morning. TY for the help!

The Green to Clean adds ammonia which eats up chlorine leaving less chlorine to battle algae. If it has flocculant in it as well that can gum up your filter.

I'm certainly not an expert on that product, but it falls in line with lots of the pool store magic potions that are really good marketing/hype, and offer promises of a quick fix, but in the long run are just a band-aid. Some of the magic potions like algaecide can cause damage to your pool.