Eliminating green algae

[spawlish]

Hi all,

I'm struggling to get my pool clear this year (my first time overwintering a pool). I have an Intex 22' x 52" ultra-frame pool with a 2500 GPH filter pump and a SWCG. I have really nasty green algae that I've been trying to get rid of. It's been clogging up my paper filters which I have to keep cleaning every couple of hours. Prior to testing, I added several bottles of standard bleach. I then tested the levels this last weekend and they were:

FC: 19 (forgot to test CC, though!)
pH: 7.6
Alkalinity: 90
Calcium hardness: 90
CYA: 40

The numbers above were produced with some "assistance" from my 5 year old, so they are a tiny bit suspect (I trust the numbers below more). Since then, I added a couple of shock treatments: 1 bottle of Clorox Shock Xtra Blue and 1 bottle of Clorox Shock Plus (yeah, I know--shouldn't have bothered, but I was getting frustrated). Today I tested again, but ran out of FAS-DPD reagent so I will order more. But, I tested the other numbers and have:

pH: 7.0
TA: 70
Calcium hardness: 80
CYA: 55

I used some test strips to test the FC and CC and they appear to be in the 10-15ppm range.

So, what now? My first thought is that I need to add sodium bicarbonate to fix TA. Then, add some calcium chloride to improve the hardness. Then, test the pH and fix that. Then what? Do I need to do all of that and then report back?

Thanks for your help!
Steve

 

[spawlish]

Oh, I forgot to mention that I tested the salt content using some test strips and it about 1300ppm. I think I need to increase that as well to about 3000ppm but I'm not sure when to do that. Now? After balancing the TA, pH, and hardness?

 

[Mr Bruce]

IMO order of importance:

1. Order more FAS-DPD reagent
2. Add your pool info to your signature please
3. If your FC is really over 10 there is no telling what your pH is. I would let it fall to below 10, adjust pH, then I would add a little bleach everyday until the FAS-DPD arrived.
4. Then I would SLAM Pool School - SLAM - Shock Level And Maintain

TA is the least of your worries.

 

[spawlish]

1. Done
2. Done I wanted to do this but couldn't find it earlier. I knew somebody would ask. Finally found it
3. Okay. A couple of stupid questions:

a. The book that comes with the K-2006 says to balance the TA first, then hardness, then pH. Are you saying my TA is close enough so focus on pH?
b. For my understanding, the reason to fix the pH before anything else is because chlorine is less effective at a high pH, right?

4. I was trying to SLAM the pool, but was just rushing... Dummy...

Thanks!

 

[YippeeSkippy]

FC is a little more effective at lower pH, but your problem is that you can't test pH while your FC is over 10. The test is not accurate and often reads "high".

Don't play with the pH while the FC is high...let it drift down and then deal with it. Your TA looks fine to me.

Please add your state to your profile, thanks! (Maryland, I assume?)