First Question from a First Time Pool Owner

[BenMc19]

Bought a house that has an in-ground pool. To my best guess it's 11-12k gallons of water. This will reveal my lack of experience, but I'm not quite sure what it's made of. My best guess is a plaster bottom, but the sides seem to be a hard smooth surface, possibly fiberglass? Does this combination make sense?

To my water chemistry, it was extremely green with a cya over 100. Did 2/3 drain and refill, got pH to 7.2, alkalinity to 100, and began slamming the pool with liquid chlorine. Within a week or so, the pool went to a very cloudy blue. My free chlorine levels will go down to 1-2 ppm, then I'll add a gallon, sometimes 2 at night, to boost the ppm to around 12. I've rinsed and repeates for a week now.

This morning i woke up and tested and the free chlorine was down to 7. So if my measurements are correct, and putting a gallon the night before increased it to 12, then i lose 5 ppm overnight, am I still need the "slamming process"?

My other questions are, to get cloudy to clear, do i keep slamming or just keep chlorine levels slightly elevated?

I feel like I'm putting a ton of liquid chlorine in the pool. Since most of you use it here, about how much do you add to the pool per day once you have it clean and clear?

Thanks for being such a great community. Looking forward to being a more active member in the future.



~11,500 gallon in-ground 27 x 13 ft
3 ft in shallow, 5.5 ft in deep
Plaster bottom/fiberglass sides(?)

 

[faby3003]

Welcome to the forum!

If you are losing 5ppm of FC overnight then you need to keep SLAMing.

To make sure you are SLAMing correctly, you need accurate numbers for FC and CYA. What test kit are you using to test your pool chemistry?

Once you have finished your SLAM, you will use around 2-3ppm of chlorine per day, so much less than you are using now.

 

[BenMc19]

Cya is 40. I'm using the Taylor k 2006.

Is it rare for me to be slamming for this long? Been about 3 weeks now that I keep putting a gallon or so a day of liquid chlorine.

Also, about the makeup of my pool. Am i just crazy when i say j have a plaster/fiberglass pool?

~11,500 gallon in-ground 27 x 13 ft
3 ft in shallow, 5.5 ft in deep
Plaster bottom/fiberglass sides(?)

 

[faby3003]

Can you post a picture of the pool?

According to the chlorine/CYA chart, your FC level should be 16 for a CYA of 40. Have you raised and maintained your FC at 16?

 

[Richard320]

Your pool is called "composite" construction. That's the extent of my knowledge of them. I've never seen one in real life.

Even assuming that you've been adding a full 128 oz of high-strength (12.5%) chlorine to your pool, that's only 11 ppm in a pool your size. If it's a 121 oz jug of 8.25% bleach from the grocery store, that's only 7 FC.

If the CYA is 40, you haven't been reaching shock level of 16, so you'll never get ahead of the algae. You may kill most of it, but then the bleach you added is gone, and what's left starts reproducing. Tomorrow you do it all again. It's futile. This is a battle to the death. You need to knock the algae down and kick it again and again and again until it's all dead.

I think it's time to reread the SLAM Process article and follow it explicitly. You'll start seeing progress.

 

[BenMc19]

Thanks for the replies. I'll make sure to get the FC up.

~11,500 gallon in-ground 27 x 13 ft
3 ft in shallow, 5.5 ft in deep
Plaster bottom/fiberglass sides(?)

 

[triptyx]

To expand on Richard's excellent post - since you have a plaster bottom, please treat your pool as a plaster pool. You'll want to keep your pH and calcium hardness in line to avoid damaging that plaster bottom. The bottom of PoolMath, once you've entered all of your measurements (including temperature), will give you the "CSI" - the calcium scaling index. You don't want that number to drop much below -0.6 or you'll risk damaging the pool bottom.

In PoolMath, don't forget to select "Plaster" as your pool type.

Welcome to TFP!