Old Bloom

[disommam]

Hey All -

I just recently bought the water test kit from TFTestkits and was pleased with how easy it was to use. Now I have a lot of great information, but still am not completely sure what direction to go in (yes, I used the chemical calculator). The root of the problem comes from an old algae bloom late last summer that I don't believe we ever were fully able to vacuum out of the pool once we killed it. (Spent several hundred dollars on chemicals to do that) When we opened the pool this year, the water was cloudy but I could see the main drains. Once we added shock, chlorine, pH up, and vacuumed the pool clarity actually became worse. I backwashed even though my PSIs have only been lingering between 8 and 12 but wanted to keep the filter clean.

After over a week of running the pump 24/7 and shocking, I'm not even close to a clear pool. My pH has been fluctuating dramatically but is currently too low. here are my numbers:
CL - 5, pH 6.8
Br - 10
FC - 12.5 CC 1.5
TC 14.0

Calcium hardness 325
TA 140
CYA 57

Based on the reading that I've been doing on your website, I think it may be best to drain the pool by at least 1/2 and use bleach and vacuum-to-waste anything left. Then re-fill the pool with tank water (vs. well water). I would greatly appreciate your opinion before I spend anymore money on chemicals OR $500 on re-filling my pool. I'm so desperate for a clear sparkling pool again. Thank you!

 

[woodyp]

Welcome to the forum. First of all, your CYA level is not in the unreasonable range. I wouldn't drain anything. Your PH could actually be lower than 6.8 and needs addressing first. Aerating the pool is easiest and cheapest way to accomplish that. You can work on lowering the Ta over time using aeration and acid. If your FC is only five, you have not actually "shocked" your pool. Read up on the SLAM process in Pool School. See the chlorine/cya chart there.

 

[tim5055]

You are confusing the tests included in the TF100. The Taylor "Basic" kit in the TF100 (that is the little box with the red tube and the yellow tube) will test chlorine/bromine and pH. Your pool does not have any bromine, so ignore that one. The limit of the chlorine test in the Basic kit is 5 (the yellow tube) so that is why you got 5 there. But, if you are using the FAS/DPPD test (powder & drops) the limit is 50, so your true FC is 12.5 - ignore the original 5 you got doing the basic test.

So, you have started to SLAM your pool, but the true shock level for CYA 60 is 24. You just need to bring the chlorine up some more and follow the SLAM procedure completely to the end.

CC is 0.5 or lower;
You pass an OCLT (ie overnight FC loss test shows a loss of 1.0 ppm or less);
And the water is clear.
When all three are true, you are done SLAMing and can allow the FC to drift down to normal levels.

 

[Azgirl71]

Sounds like you need to start SLAM process like Tim said. Remember it takes time and patience. I did not think my pool was that bad, but it was and took me just shy of 2 weeks to finish my SLAM.

 

[Casey]

Get your pH up first to 7.2 befor you start your SLAM.

Welcome to TFP.

 

[Divin Dave]

Hi disomman,
your numbers are not too bad. You do not need to drain any water.
The fact that your water is cloudy and you hace CC of 1.5 says that you have active organics in the pool which is consuming the chlorine.
that old alge is not all dead.

to cure the pool, you need to SLAM it as Tim mentioned.
Here are the instructions
http://www.troublefreepool.com/content/119-how-to

The SLAM is not a one time miracle cure. There is no such thing. It will take regular testing and dosing of chlorine to maintain the SLAM FC level of 24.
Here is the FC/CYA CHlorine chart. You will need to reference this for as long as you own your pool.
http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

Armed with this info, a test kit and pool math, you can bring your pool back to sparly and clear and be able to keep it that way. Here are the recommended levels for when you finish up the SLAM.
http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

 

[disommam]

Thank you all! I'm working on getting the pH up and will be more precise with the slamming process. As of today, there is dead algae on the bottom of the pool and I think I will vacuum that to waste. The water is clearer so, yes, this process is taking a long time and I need to be more patient.

 

[Azgirl71]

The SLAM process does require patience but the payoff in the end is worth it.

 

[Casey]

Maintain the high chlorine level and you'll get rid of that bloom and enjoy the pool!