Drain and refill pool recommendations

[james123]

My first post...

I am preparing to drain and refill my pool due to sky high TA and CYA levels. I had a couple of questions on this:

1) Is it a good idea to always do a chlorine bath prior to refilling? The pool looks fairly clear except for some recent green at the water line that I suspect is due to low chlorine level. If this should be done, what is the recommended chlorine concentration to use, and what would the technique be? I've seen some videos where a watering can was used, followed by a simple hosing down with water. Is there anything else cleaning-wise one should consider while the pool is drained?

2) After the refill, what is the generally recommended order of doing things as far as chemicals go? By this, I'm wondering about the order for getting pH, chlorine, TA and CYA up to snuff. FWIW, I plan to use regular old bleach going forward to avoid the crazy CYA levels.

Thanks!

10K IG Pebble Tec DE 2HP

 

[jblizzle]

Welcome to TFP!

I would say the chlorine bath is optional. If you had algae, then it is likely in the pipes and equipment so you will need to follow the SLAM process after the fill anyway. Do you already have one of the recommended test kits?

After you fill, test the pH, TA and CH to find out what needs adjusting.

You will need to add around 30ppm of CYA, get that dissolving in a sock first and get around 3ppm of FC in there too. Then post up your test results to see what is next.

 

[bobodaclown]

Welcome to the forums.
What is your current CYA level?
What is your current TA Level?
You need some CYA in your pool. So you don't need to drain all the water. Just need to get it to a manageable level. For example if your CYA level is 100 you need to drain 70% of it to get it to 30%. It's not all, but it's better than having to drain it all. Because you'll have to add some CYA anyways.

What's the TA of your fill water? You can lower your TA using acid and that can be done over time. Living in AZ, you know the value of water, and I'd hate to see you waste your money.

You can use POOL MATH http://www.troublefreepool.com/calc.html , punch in your current levels and it will tell you how much water you'll need to replace.

Don't forget to check out pool school. http://www.troublefreepool.com/content/

 

[james123]

Thanks for the responses, folks, makes sense on raising CYA as a first step, and then adding chlorine. The test kit is a Taylor K-2006. Following the "pour the solution in till the black dot disappears" instructions, I didn't even get to the 100 CYA marking-- I would say a half inch below that. Unless I did something wrong, I believe this indicates I'm WAY higher than 100 ppm. TA level was 220. I think the pool caculator had me replacing 90%, so I suppose I could leave just a little.

I'm also planning to clean out the DE filter as pressure is high. Would it be best to do this before or after the pool refill?

 

[Patrick_B]

Welcome James!

It does sound like drain time for that Cya level. I don't think it matters much, but if it were me, I'd go ahead and do the DE filter sometime before I re-filled.

 

[jblizzle]

You can get a better idea of the CYA level, but starting the test with 50/50 mix of pool and tap water and then doubling the result ... you are likely WAY over 100ppm.

If you do not drain 100%, then after the refill, circulate the water for an hour and do a full set of tests, you may not need any more CYA before starting the SLAM process.

 

[james123]

Putting everything together, I'm going to go for a 90% drain and refill. Hopefully this will get me to around 30 ppm CYA. At that point, I will get FC up to 3-4 ppm. If I understand correctly, I should observe for FC loss at this point. If observed, it would be an indicator that SLAM is needed?

I am going to attempt this over the weekend, and will post back results. Thanks again for the responses.

 

[jblizzle]

It is normal to lose 2-3ppm of FC every day. That is why you have to test and add bleach daily.

You need to SLAM if there is any visible algae, CC more than 0.5ppm, or if you observe higher than normal daily loss.

 

[Patrick_B]

Good luck, and let us know how it goes.

 

[Theep]

Bump

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