All numbers within spec , why alage??

[igbig]

Hello all! Longtime lurker first time poster. I have a 2 year old, in ground pebble tech pool. I take care of it myself and have done well overall with the exception of CONSTANT high PH that i still struggle with. I leraned the hard way thanks to this site about the problem with using pool store pucks to chlorinate and building up waaaaay too much CYA. My pool is always sparkling and hass never been cloudy. I run a Dolphin Triton 2 just about everyday so the pool stays pretty clean. I try to brush the walls and steps at least twice a month. I never let anything float or sit on the bottom of the water that doesnt belong there. I am pretty anal about keeping the pool clean. I use a TF100 kit to test my water, again thanks to you guys.
I was hoping you cold help me with a problem that has arose. I have started to get a little green algae on one wall and on a step and a seat where they meet the pool floor. its not much but i cant figure out why I am getting algae it since my last test showed all of my numbers in good range. We have not used the pool for 2 months so swimmers are not an issue. any ideas? Thank you in advance!

here are the readings

FC-1.5
CC-0
TC-1.5
CH-300
TA-120
PH-7.6 (this is after a half gallon of muratic acid two days before)
CYA-58

Does my chlorine need to be higher? I only use one puck in the in-line chlorine disolver becsue i m aleery to use too many since the CYA issues i had. should I put in a gallon of bleach? HELP!

 

[Jimrahbe]

ig,

Welcome to TFP... A Great resource for all pool owners who have "spec" issues...

Well, there really is no magic here.. To prevent algae you just need to keep your FC per this chart... [FC/CYA][/FC/CYA]

Your FC is waaaay too low. Looking at the chart, with a CYA of 60 the very minimum FC is 5 with your target between 7 and 9. Your FC is 1.5...

So... my question to you is.. why do you think your numbers are "within spec"???

Thanks for posting,

Jim R.

 

[richierich]

Also keep in mind algae's favorite hiding spot is in our around ladders. I had my numbers all summer perfect (exactly what was on the CYA/FC) chart and still had small spots of algae under my ladder. I Guess the ladders block the circulation of the pump pool water. Just make sure to brush there often.

But yes, your FC is wayyy too low

 

[duraleigh]

Once you begin to understand the principles of TFP, you realize that numbers are only guidelines....not hard-set absolutes.

If you have visible algae, your numbers are not "perfect". You need more chlorine or, in some cases, better circulation. It's most always inadequate chlorine that produces algae.

 

[Catanzaro]

Hello all! Longtime lurker first time poster. I have a 2 year old, in ground pebble tech pool. I take care of it myself and have done well overall with the exception of CONSTANT high PH that i still struggle with.

Your TA of 130 needs to come down. Once the TA comes down, you will have an easier time managing PH. Unless that is your fill water is the culprit here.

I try to brush the walls and steps at least twice a month.

It is recommended you bump this up to at least weekly. If algae spots continue, then you may have to brush twice weekly. You state that you "try". Is it possible that you have done less?

I use a TF100 kit to test my water, again thanks to you guys.

Hopefully you have the speed stir. Although, you claim that the CYA level is at 58. Sounds to me like this could be a pool store type of test result.

I was hoping you cold help me with a problem that has arose. I have started to get a little green algae on one wall and on a step and a seat where they meet the pool floor.

Acitivity sometimes is better than no activity, especially with a properly chlorinated pool. You would be circulating the water more often. It is possible that you have circulation issues? How many skimmers, main drains, returns do you have in the pool? Maybe changing the direction of the returns would help with some dead spots. If the problem persists, you may want to look into rotating circulator type of returns. Although, with a high TA of 130, these type of returns will only drive your PH even higher and faster. You may just consider brushing more often.

FC-1.5 Does my chlorine need to be higher? I only use one puck in the in-line chlorine disolver becsue i m aleery to use too many since the CYA issues i had. should I put in a gallon of bleach? HELP!

Yes, your chlorine needs to be within range and needs to stay within the range as mentioned earlier. This could be your only problem. The key is not to just haphazardly throw chlorine in the pool. Use Pool Math to figure out how much chlorine you need to add to get your levels to the minimum required based on your CYA. What you may want to do is bring the pool up to shock level (SLAM) for 2 full days (pump running & brush daily), and then perform the overnight test. Once you pass the test, then stay on track with the recommended levels and brush at least once a week to start. If you fail the overnight test, allow the FC levels to come down to under 10 and then perform the test again.

For the first week, you may want to test each day to have an idea on how much chlorine you are burning. Then weekly, make adjustments if you are over. Good luck and keep us posted!