SLAM green pool without FAS/DPD kit.

[ahnjoan]

First wanted to say thank you for troublefreepool.com and all of those that participate. I've learned more in the last two weeks reading than I thought was possible. I have been struggling with a green pool.

Short version...
Green pool...
I added way too much stabilizer (CYA > 200ppm with tap water dilution) and have drained the pool to get the CYA down to between 30..40.
I have a FAS/DPD kit on the way (K1515A) but have the DPD kit already.
I tested for Chlorine this morning after it was filled back up and it reads FC & TC at both 0.5 or lower.
My FAS kit doesn't get here until Thursday and I'd like to start the SLAM today.

Question - Is there any reason I shouldn't rely on the readings from my DPD kit and begin slamming?

I think I'm using the calculator correctly. With a 1,700 gallon pool, to go from .5 FC to 16 I will need to start with 38oz of 8.5% bleach.
I'll also verify PH before I start but I didn't think of testing for that this morning since I have had such high Chlorine numbers for weeks and it didn't occur to me now that the CYA and Chlorine are down the test would be valid.

Thank you
Ahnjoan

 

[JVTrain]

I wouldn't recommend starting a SLAM without a reliable way to test FC/CC properly. You can prevent it from getting worse and get a slight start by adding about a quart per day until it arrives.

You'll want to be able to recheck pH before starting the SLAM in earnest so don't go wild with the bleach before the kit gets there. No sense flying blind, but you can keep it from getting worse.

 

[ahnjoan]

I wouldn't recommend starting a SLAM without a reliable way to test FC/CC properly. You can prevent it from getting worse and get a slight start by adding about a quart per day until it arrives.

You'll want to be able to recheck pH before starting the SLAM in earnest so don't go wild with the bleach before the kit gets there. No sense flying blind, but you can keep it from getting worse.

Not trying to be rude at all by not taking the advice but I was impatient and my k-1515 was so far out from delivery. As it stands now, I've cancelled the k-1515 delivery and ordered it again on amazon from another vendor who shipped today.... So I'll be a FAS/DPD convert as soon as it gets here. But... I have moved forward with the DPD (maybe blind) test SLAM. Im including all of the data I've put together. The night time change in Chlorine seems fairly low, and the pool looks very good. The problem is the TC is always so high (shows on the DPD test). From that I assume CC is far above the 0.5 requirement to be finished.

I'd love anyones thoughts on why CC is so high.

I've attached a PDF of all of my testing and treating information along with dates and times of applications.

View attachment info.pdf

 

[jblizzle]

Warning, the DPD test can bleach out at high FC levels. You may think it is low or zero when in fact it is really high.

I have to ask. With a 1700 pool, why not drain and start over? Faster and cheaper.

 

[Richard320]

Not trying to be rude at all by not taking the advice but I was impatient and my k-1515 was so far out from delivery. As it stands now, I've cancelled the k-1515 delivery and ordered it again on amazon from another vendor who shipped today.... So I'll be a FAS/DPD convert as soon as it gets here. But... I have moved forward with the DPD (maybe blind) test SLAM. Im including all of the data I've put together. The night time change in Chlorine seems fairly low, and the pool looks very good. The problem is the TC is always so high (shows on the DPD test). From that I assume CC is far above the 0.5 requirement to be finished.

I'd love anyones thoughts on why CC is so high.

View attachment 68340

If you used any kind of non-chlorine shock aka MPS, it will show up. Or you've bleached out the DPD. Or you really have super high CC, which could be from CYA breaking down into ammonia. But these are all conjectures. A proper diagnosis requires accurate test results.

 

[domct203]

If you do decide to SLAM the pool, you will chew through those 0.75oz bottles of reagent quickly. It would be wise to order replacements now.

http://tftestkits.net/XL-Option-p62.html

 

[ahnjoan]

Warning, the DPD test can bleach out at high FC levels. You may think it is low or zero when in fact it is really high.

I have to ask. With a 1700 pool, why not drain and start over? Faster and cheaper.

I did end up draining more than half of the pool, prior to the data shown in the attachment. That was to get my CYA down. The assumed though that draining the pool entirely wouldn't really fix the algae issue since it is in the filter and all the other wet parts of the pool. From my math, filling the pool costs around $20, if I could have drained it 100% and refilled I certainly would have over all the money I've spent. Do you think I could have solved the algae problem by just draining and restarting?

- - - Updated - - -

If you do decide to SLAM the pool, you will chew through those 0.75oz bottles of reagent quickly. It would be wise to order replacements now.

http://tftestkits.net/XL-Option-p62.html

Thanks, I'll certainly come back here when I need refills.

 

[jblizzle]

Sure, you drain the pool. Wash the pool down with a bleach solution. And then fill it back up. And balance it.

Have you read the Pool School - Guide for Seasonal/Temporary Pools ? That is one way to maintain a small pool. But, with the good test kit, you can do a little better job and have a better chance at ensuring it stays clear.

 

[ahnjoan]

If you used any kind of non-chlorine shock aka MPS, it will show up. Or you've bleached out the DPD. Or you really have super high CC, which could be from CYA breaking down into ammonia. But these are all conjectures. A proper diagnosis requires accurate test results.

Thanks you for the reply, I haven't used any MPS so I don't think that is it. I also think the CYA to ammonia is unlikely since the CF & FC were very close (within .5) right before I started the SLAM. I don't know what "bleached out the DPD" means, but I assume that is possible since someone told me at the office today that I put way too much bleach in during the SLAM and that is the cause of the grimy looking yellowish stains in the very low spots of the pool floor. I've tried to scrub them with the brush but the uneveness of the pool floor makes it difficult. Once I can get back into it I'll try scrubbing them more.

 

[ahnjoan]

Sure, you drain the pool. Wash the pool down with a bleach solution. And then fill it back up. And balance it.

Have you read the Pool School - Guide for Seasonal/Temporary Pools ? That is one way to maintain a small pool. But, with the good test kit, you can do a little better job and have a better chance at ensuring it stays clear.

Thank you for the response, I hadn't read that but I will take a look now. Really the purpose of this pool is to prove to myself I can handle the work that comes with a real pool before investing a lot of money. I'm enjoying it... Surprisingly... since it has been a bit of a time suck in the last two weeks.

 

[jblizzle]

Pool are similar to aquariums in that often the smaller they are, the more difficult they can be to maintain.

You have a decent filter already so that certainly help with the maintenance. And quickly you will have control of the chemistry. It is all the same with a larger pool ... just requires more of the same chemicals and more time brushing

 

[ahnjoan]

Pool are similar to aquariums in that often the smaller they are, the more difficult they can be to maintain.

You have a decent filter already so that certainly help with the maintenance. And quickly you will have control of the chemistry. It is all the same with a larger pool ... just requires more of the same chemicals and more time brushing

Thank you for your response, I'm taking to heart the last part of your comments now. My makeshift vacuum and brush are barely usable. Now that I can see the bottom of the pool there is quite a bit of brushing to be done.

On the larger topic... My last two tests have shown CC way down, TC and FC almost identical in both this mornings test and this afternoons with no treatment. I think I'm back in the blue/white... Thanks again for all the help. TFP is a huge time saver!