Pool turned green after heavy rain

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S

Sarahdeakins

0
Aug 12, 2016
56
Houston TX
Went to sleep with a clear, sparkling pool. We had extremely heavy rain overnight (in Houston, TX) and woke up to a cloudy green pool.


i have been battling what I believe is mustard algae around the pool steps. I slammed it this weekend. Right now my FC reads 12 (coming down from the target slam of 20, due to cya being 50). CC is 0. I'm surprised given the chlorine reads I have a problem. I don't think the pool ever overflowed, but I guess I can't rule it out entirely. I woke up and it was close to overflowing at that point so I drained it enough so I could get the filter going. Any advice?
 
Chemical readings
FC 6.5 (I think I added the r-0871 too quickly when I got the previous reading. I retested 3 times swirling the additives each time and have gotten as low as 5.0 but got 6.5 twice, so lets go with that)
CC 0
pH 7.2
TA 70
CH 325
CYA 45
 
Hi Sarah! :wave: We certainly have been hit with some rain these past couple days. It is odd to see such a drastic change in water color. A heavy rain alone won't just do that, so perhaps whatever you had brewing in the water before simply woke from its slumber during the storms. In either case, I suspect you know the remedy ..... SLAM. It is important however to ensure you are comfortable with your testing to ensure an accurate reading. If your sky is overcast and dreary like ours in S.A., you can't validate the CYA, so we'll assume it's still 50. For the FC testing, make sure to use the 10ml water sample, add one hefty scoop of powder (doesn't have to be perfect), start swirling and multiply drop count by 0.5 (basically divide by 2 - standard method). So if you go from Barbie pink to clear in 12 drops, your FC is 6. I always have HEB's Bravo bleach handy, but you can also use the Wal-Mart products (Great Value or Pool Essentials). Just make sure the bleach is regular/plain.

Your pH is perfect for a SLAM, so I'd just increase the FC to 20 and maintain as best as you can throughout the day and make sure to brush each day. If your filter pressure increases by 20% or so, do a backwash. If you have ANY potential hiding places in your pool (behind lights, under steps, etc), make sure to clean those areas as well. Even check under your poolside skimmer cover for algae. I had some under mine a few weeks ago.

I would also suggest reviewing the SLAM page (link below) once a day as a memory jogger to ensure you've covered everything. Hang in there until you pass the 3 SLAM criteria and you should be fine. If you have any more questions, please let us know.
 
OTPirate, I'm using the tf-100 test kit and have updated my signature.

Pat, thanks. You must be right, I'm just so puzzled by it. The shallow end is already clearing up a bit and I don't see any spores or gunk (for lack of a better word) on the walls or tile. It's like the water is cloudy with a green tint, but the pool is clean. I just dropped the robot in the pool in case there's debris on the bottom, and I can't even see the robot! I checked the waterfall reservoir too and it is clear as well.

I just so happen to have 8 gallons of Bravo bleach in the garage so I will review the SLAM page again and get going. Thanks for your help.
 
LOL I like your style! :hug:

Okay so you have algae. BUT you have the best test kit out there. You also have some bleach. Print out the SLAM page and get to work.

Try to test and add at least 4 times a day. Brush at least once a day. Filter on 24/7 until done.

A picture a day looking down at your steps to help you and us watch it clear. It will help you see the SLAM as it works.

Kim:kim:
 
Update. And follow up question.

Pool | Flickr

the pool is back to beautiful. I held the chlorine to 20+ ppm overnight. About 10 hours into SLAMMING the filter pressure jumped way up so I was backwashing the filter at midnight last night. ;)

Woke up this morning and it looks almost perfect. I'm seeing traces of what I assume is conquered algae on the pool floor so I need to vacuum that up. QUESTION: Are you supposed to switch your filter to waste mode when you vacuum alager or does it matter? Does this keep you from dirtying the filter? I assume your losing water though right?

Going to hold the chlorine to SLAM levels and run the OCLT tonight. Wish me luck and thanks for the help!
 

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WOW! That fastest SLAM ever!

Vacuuming-I like to vacuum to waste as it makes me feel good to get the stuff OUT of the pool and filter. Of course that DOES mean I have to add water and work on getting it all mixed and balanced again but it is worth it to me. You can vacuum to the filter. That does mean you may have to clean your filter sooner than if you went to waste.

Kim:kim:
 
Update: that was not algae after all. It appears I have a drainage issue just to the right side of my pool. Groundwater is collecting and overflowing into the pool. I was lucky to be home this afternoon during a quick but heavy downpour and saw the pool turning brown in the area of concern:

IMG_7137 | sarah deakins | Flickr

We have only been in this house since July but we have never had this issue before. I'm hoping we can get this addressed easily!
 
What are the chances you were home AND looking right when that started to happen! Nice job! I hope you can fix it fast.

When the rain is over maybe take pics of that area and poke around and see what you can find. Good luck!

Kim:kim:
 
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