Got my numbers, ready to SLAM. Please help, this is my first time needing to.

[aaroncp]

26' Coleman Above Ground with Intex Sand Filter and Intex SWG.

FC = 14
CC = 3
TC = 17
Ph = 6.8
CH = 125
TA = 40
CYA ~ 110 (diluted CYA test)

Am I right in thinking I'm heading towards at least a 20% drain here because of the insane CYA level? What in the world caused those CYA levels? I thought the sun burned CYA off and it's been crazy hot here for the last few weeks.

 

[Texas Splash]

So a SLAM it is! First though, while you know the CYA is high, you might want to find out "how" high over 100 it is. Consider doing a diluted CYA test as seen on the Pool School - CYA page starting at step #8. Once you know your true CYA, exchange the proper amount of water. While you typically run a higher CYA (70-80) for a salt pool, for the SLAM a lower CYA (30-50) will require less bleach. So it's up to you. But definitely get the CYA lower.

It had to get that high from stabilizer - over-dosed or using stabilized products like tabs/bags of shock. So avoid those in the future. Your pH and TA are a bit low, so I would consider increasing the TA to about 50-60 at a minimum and the pH to 7.0 before starting the SLAM. Good luck!

 

[aaroncp]

I did the diluted CYA test and got ~110.

 

[Texas Splash]

I did the diluted CYA test and got ~110.

Great! So with a confirmed CYA of 110, if you exchanged 50% of your water your CYA should go down to about 55. Much better for a SLAM.

 

[aaroncp]

Great! So with a confirmed CYA of 110, if you exchanged 50% of your water your CYA should go down to about 55. Much better for a SLAM.

Yikes, I was hoping for less but I guess I'll start draining. I did a small drain the other day after it rained and it killed everything around the where the water comes out the backwash hose. HUGE area of dead grass. Guess that's the acid?

 

[Texas Splash]

Guess that's the acid?

We've had discussions about grass before. Hard to tell. Different grasses, amount of moisture in the soil, acidity of the pool water, etc. I think it all plays a part in how it effects the lawn.

 

[aaroncp]

Is this water safe enough to get into and vacuum and scrub the walls while it drains? There is a lot of dead algae on the bottom (I attempted a shock earlier in the week with three gallons of bleach -- I'm just now noticing the water itself isn't green it's the bottom of the pool) and I'm vacuuming a lot of it directly to waste as it drains, but I can't reach it all with my pole. Wondering if being in it for a short amount of time will be harmful.

 

[Texas Splash]

Yes. As long as your FC doesn't exceed the SLAM/Shock level for your current CYA, you're fine. [FC/CYA][/FC/CYA]

 

[aaroncp]

Here's my new numbers after draining and refilling overnight.

FC = 6
CC = 0
TC = 6
pH = 6.8
CH = 100
TA = 30
CYA ~ 60

Proceeding to raise pH and TA to needed levels.

 

[aaroncp]

And that's done.

Added the calculated amounts of baking soda and borax. pH is now at 7.8 and TA is at 80.

Going to wait until sundown to bring the pool up to shock level.

 

[Texas Splash]

Nothing worse that "back & forth", but it looks like you raised the pH too much before the SLAM. You'll want to lower the pH to about 7.2 before increasing the FC to SLAM/Shock level.

 

[aaroncp]

My digital pH meter is saying 7.3. The little blue box in the TF-100 kit shows ~7.8 by the color chart, which is the one I recorded. So I made sure my digital reader is accurate with a control sample that came with it, and it is accurate, so I'm going with its reading. Not sure I like those match-color test kits. I'm going with my digital meter.

 

[Texas Splash]

My digital pH meter is saying 7.3. The little blue box in the TF-100 kit shows ~7.8 by the color chart, which is the one I recorded. So I made sure my digital reader is accurate with a control sample that came with it, and it is accurate, so I'm going with its reading. Not sure I like those match-color test kits. I'm going with my digital meter.

I understand. We are very cautious here at TFP about digital meters simply because of the potential calibration issues that can happen - even with a test sample provided. The 5-drop (R-0014) pH test is fairly foolproof, while I will admit it gives my eyes some frustration at times. Something I have been doing recently is adding only 4 red drops to the comparator view as sometimes that helps me differentiate the shades a bit better, then I'll add the 5th drop just to compare once again. Figured I'd put that out there for you if you wanted to try. There are also YouTube videos on the pH test which you might find helpful as well. So while I don't mean to knock the digital pH test, just be careful.

 

[aaroncp]

Some photos thus far:

Pre-shock (Friday)

Day 1 (yesterday)

Day 2 (this morning)

Added some DE to my filter last night to help clear the pool more quickly. Very little green left in pool, mainly in the middle where it's hard to reach with vacuum. We Macgyver'd our vacuum pole to a rake to be able to reach all the way in. I haven't vacuumed yet this morning so I'll get the few spots left in the center here shortly.

Very pleased so far. I think another 24 hours will see even more improvement in the water clarity.

 

[Texas Splash]

Wow! Great job. That first photo (green) had me a bit worried, but it's clearing up nicely.

 

[jalexa101]

Wow! Great job. That first photo (green) had me a bit worried, but it's clearing up nicely.

It kind of looks like mine with a tint to it. Perhaps pics or shadows do alter or make it hard to determine.

AaronCP - it appears you are on your way - how much bleach did you have on hand? Your pool is slightly larger than mine.

 

[aaroncp]

AaronCP - it appears you are on your way - how much bleach did you have on hand? Your pool is slightly larger than mine.

I started with nine gallons on hand, only because that was all I could get my hands on that morning. This photo includes the gallons I added one per day while waiting for my TF-100 kit to arrive.

In a weird way, this has been fun so far. I wouldn't want to have to do it again, but I like the chemistry of it all.

 

[Texas Splash]

In a weird way, this has been fun so far. I wouldn't want to have to do it again, but I like the chemistry of it all.

How about the look on the cashier's face when you checkout? Just add some duct tape and plaster bags to that purchase and you really make things interesting.

 

[aaroncp]

How about the look on the cashier's face when you checkout? Just add some duct tape and plaster bags to that purchase and you really make things interesting.

Oh, man, I know! We have nosy neighbors and they probably thought I slaughtered the whole family. Thankfully we all made an appearance on the porch this morning at the same time, so here's hoping no detectives show up.

 

[aaroncp]

Lost 1.5 FC overnight! The end is in sight!