Green water & high Ph

[Cowbell]

Noticed through my clear cover some green coloring so I put the SWG on boost and let it crank while I was away for a week. Returned to a still light-green pool, here were my settings earlier today:

FC: 6
CC: .5
TC: 6.5
CH: 100
TA: 50
CYA: 25
Ph: 7.7

Off to the pool store for some shock. I usually use liquid shock but was told 1lb of 73% Calcium Hypochlorite super-shock granules would do the trick. He also said my Ph was too high and tried to sell me some pricey Ph reducer but I thought I'd run that by TFP ...

I added the 1lb of shock and now numbers are:

FC: 14
CC: .5
TC: 14.5
CH: 100
TA: 50
CYA: 25
Ph: 7.8

I am slowly adding CYA granules to get my CYA up. My question is, what should I do about the Ph and TA? I have never had to adjust those numbers and as I'm shocking I didn't want to do anything rash.

Pump is running 24/7 although I turned the SWG off for the night as 14 FC seems pretty high. I'll check again in the morning and if FC drops (expected) I'll use the SWG boost to get it back up and keep it up until the green is gone. Please correct me if this isn't a good plan.

Thanks for any advice!

 

[mknauss]

You need to SLAM Process. Read the article and follow the steps. Use this [FC/CYA][/FC/CYA] for your shock level.

Your pH test is invalid with FC above 10.

Take care.

 

[Cowbell]

I am SLAMing - that's why I raised the FC to 14 which is appropriate for my relatively low CYA as per the chart you linked.. My ph was 7.7 before I added the Calcium Hypochlorite.

 

[mknauss]

Great. In the article for the SLAM Process it states to lower your pH to 7.2 before starting the SLAM.

Also - be aware that Cal - Hypo add calcium that you cannot remove from your water without draining. High CH is still a problem with a vinyl pool and especially a SWCG.

Take care.

 

[YippeeSkippy]

One dose of granular Cal-Hypo does not a SLAM make. Liquid chlorine, aka bleach, would probably have been a better choice. Keep testing and re-dosing througout the weekend to keep your FC up to SLAM level and slay that green beast!

Maddie

 

[Cowbell]

Thanks for the replies. I might not have been clear on my original question. I do appreciate that I should have taken care of lowering pH before shocking, but the delorean is in the shop so I'm wondering what, if anything, I should do about elevated pH at this point?

 

[Cowbell]

Edit: made a rookie testing mistake. FC is at 12ppm at 1pm

 

[YippeeSkippy]

Let the FC drop to just under 10 and then test pH. Treat pH if necessary then continue on with the SLAM process using bleach or liquid chlorine.

Maddie

 

[Teald024]

still light-green pool, here were my settings earlier today:

FC: 6
CC: .5
TC: 6.5
CH: 100
TA: 50
CYA: 25
Ph: 7.7

Off to the pool store for some shock. I usually use liquid shock but was told 1lb of 73% Calcium Hypochlorite super-shock granules would do the trick. He also said my Ph was too high and tried to sell me some pricey Ph reducer but I thought I'd run that by TFP ...

I added the 1lb of shock and now numbers are:

FC: 14
CC: .5
TC: 14.5
CH: 100
TA: 50
CYA: 25
Ph: 7.8

I am slowly adding CYA granules to get my CYA up. My question is, what should I do about the Ph and TA? I have never had to adjust those numbers and as I'm shocking I didn't want to do anything rash.

Pump is running 24/7 although I turned the SWG off for the night as 14 FC seems pretty high. I'll check again in the morning and if FC drops (expected) I'll use the SWG boost to get it back up and keep it up until the green is gone. Please correct me if this isn't a good plan.

Thanks for any advice!

Best advice is to stay out of the pool store, they are doing you a great disservice.

You should turn your SWG off and only use bleach/liquid chlorine for the SLAM. Save some life on it.
The 1 lb of Cal Hypo only raise your FC about 5 ppm in your pool. It's not the best choice as it will add adtl calcium also.
Use muriatic acid to lower the pH. Much cheaper than the $tores high-priced pH reducer. The dry acid will add sulfates that isn't good for the SWG. Normally a pH of 7.8 is on the upper end but not necessarily need to be reduced. Since you are doing a SLAM, you should drop it to 7.2.
TA of 50 is fine, leave it alone for now. It will drop further when you add the acid though. Revisit it after you finish the SLAM.

 

[Cowbell]

Thanks all. In the past 2 days the pool has become crystal clear, although FC is still on the high side at about 18 so I'm running cover-off swg-off to help burn it down through today, hoping to get it under 10 to swim soon.

pH is at about 7.6 right now and I haven't done anything else except add maybe 500gal of tap water. I wish I could buy a tiny amount of muriatic to edge it down a smidge.

CYA is still stubbornly low at 25. Wonder if the granules I bought at Walmart a couple months ago were bad...