Attempting to SLAM and want to do it right

Jump to latest Follow Reply
D

Dfraz

0
Aug 27, 2014
8
NJ
First year taking over the pool and it has not gone as well as I hoped. I've been fighting algae problems recently, due to time away from home, and the stores have not helped me out at all. I've managed to read enough here to get started, but may still have some things wrong. The algae is currently light in color and amount.

I tested and here are the numbers:

FC - 2.5
CC - .5
AK - 130
CH - 160
CYA - 100
Ph - 7.5

Here is what I plan to do:

- Replace the water with 60% new water. Got this from the calculator.
- Brush/Vacuum as best as possible
- Get the Ph to 7.2
- Test the FC and go nuts with the bleach, checking at least twice a day and adding as needed especially in the beginning
- Backwash/Clan the filter as needed

I would then be looking for CC at .5 or lower, pass an OCLT and the water is clear.

If there is anything I'm missing or I've got something completely wrong I'd like to know before I get started. Any suggestions are welcome as well. Thanks for building the great site and am looking forward to learning how to take care of my pool properly. Sorry for the length, wanted to make sure I was thorough. Thanks!
 
:wave: Welcome to TFP!!!

Sounds like a pretty good plan ... except for the "go nuts" parts ;) Always test and dose to the appropriate level using PoolMath ... although I think you understand that.

Backwash the filter when the pressure goes up 20-25% over the clean pressure.

What test kit are you using?
That CC number does not make sense. The FAS-DPD tests in increments of 0.5ppm.
 
Thanks for the quick reply!

I meant to put .5 for the CC. sorry for the confusion. I've fixed it now.

Another question, It has been a very mild summer and is already almost time to close up the pool for the winter sometime next month. Is it worth slamming or should I just close it and open it with a SLAM next year or will it make the problem worse?
 
Well, if you SLAM now and close and open in the spring properly (see Pool School), then you will open to a clean pool. Or you can always let the pool go green and deal with it in the spring ...
 
Good! You have your own test kit. That is a good start!

I would SLAM it just because I THINK it would make it easier to open next Spring. I am not sure if there is any truth in my thoughts but...................I would have to at least try to close it clear and clean.

Kim
 
After you get your pH set to 7.2, and start adding bleach for the SLAM, you do not need to do a full round of tests, do just FC and CC. It will save on your regents.

We would like pictures... Before, During, and After. You can even be doing a happy dance in the After pics...... lol..
 
I think it would be a good ideas to SLAM before closing. The algae will live on until the water temp drops below 60F and so you'll be better off in the spring if you kill it all now. Otherwise it grows and dies over winter and the water is just a soup of dead algae and organics which can stick to and stain your liner.


Sent from my iPhone using Tapatalk
 

Enjoying this content?

Support TFP with a donation.

Give Support
Sorry for not updating sooner, having enough problems finding time to make sure I test the pool enough during the process. I have kept notes throughout and believe I may be done or close to it. Here is everything I have recorded. It's possible I forgot to write one down but the chemical amounts were always correct to take it to the required Shock FC level.

The first thing I did was drain the pool and replace at least 60% of the water with new water.

Here are two pictures of the pool before it was filled back up.
http://i.imgur.com/48jwCOT.jpg
http://i.imgur.com/inzyXCh.jpg
(not the best but you get the idea)

after the pool was filled back up these were the results.

FC - .5
CC - 0
CYA - 50 (only thing I tried to change so far)
CH - 140
AK - 90
PH - 7.0

I brought the PH up to 7.2 as recommended and after that added the bleach to bring it up to 20 FC (based on the 50 CYA level) I used the liquid shock from the pool store as it's 12.5% instead of 6%.

I tested the FC and CC going forward since I started this process on Sunday (8/31). My times are a bit strange as my work schedule varies.

Sun 9:30am
FC - 7 (brought it up to 20)
CC - 0.5

4:30pm
FC - 7.5 (brought up to 20)
CC - 0.5

10:15pm
FC - 12.5 (left as is to test overnight loss)
CC - 0.5

Mon 8:30am
FC - 10 (brought up to 20)
CC - 0.5

4pm
FC - 5.5 (brought up to 20)
CC - Don't have this one, someone else tested for me, seeing the trend I assume 0.5

11:30pm
FC - 14 (Left it at 14)
CC - 0.5

Tue 8am
FC - 12.5
CC - 0.5

7:15pm Decided to check CYA again as the water was looking much clearer.
CYA - 30 (Shock FC level is now 12 instead of 20)
FC - 10 (brought up to 12)
CC - 0.5

9:30pm
FC - 10.5 (left it to test overnight)
CC - 0.5

Wed 9am
FC - 11.5 - This seems strange as it increased the FC by 1 and I didn't add any bleach. I can only guess this is because it rained overnight.
CC - 0.5

9:15pm
FC - 6 (brought up to 12)
CC - 0.5

At this point I took some more pictures.
http://i.imgur.com/GPjLVeL.jpg
http://i.imgur.com/Hbmt8gx.jpg

Thu 11 am
FC - 8.5 (brought up to 12)
CC - 0.5

8:15 pm
FC - 6.5 (brought to 12)
CC - 0.5

Fri 10:15 am
FC - 9.5
CC - 0.5

My last test shows an overnight loss of 2.5, however the sun had been out for a few hours at this point.

Should I continue to bring the FC to 12 and wait for a perfect overnight loss test are does this seem like it's on track and I can let it come down to the regular level.

Thanks again for everyone's help!
 
timerguy said:
And the morning test needs to be done before Sunrise if not, it's pretty much invalid.
Click to expand...

I wouldn't say "before the rooster crows" as my pool is shaded until about 8:30am. I think morning light is ok as long as the pool water has no direct sun light in it.

However, if the pool gets sun immediately, then it's definitely before the rooster crows ;)


Sent from my iPhone using Tapatalk
 
I did backwash the filter at one point, but how long should I do this for or how do I know when it is done?
Edit: the water was clear coming out during the backwash.

Also my pool stays shaded until about 9:30 since the sunrise hits the front of the house. It's tougher for me to wake up any earlier since I work late nights, but I will do what I can.
 
Well, normally you should record your starting pressure and then backwash when the filter pressure gauge reads 25% over START pressure. Most filter gauges have a rotatable plastic face ring with the words "START" and "SERVICE" printed on it so you can mark your starting point.

When SLAMing, I typically backwash my DE filter when I hit 20% over nominal because your killing so much algae and generating so much waste that it just works better.


Sent from my iPhone using Tapatalk
 
Anytime I have looked at the filter it is between 20-25%. Before and during the slam. It has never changed unless I backwash/waste/rinse whatever. It drops but then when set to filter it's back up to the 20s.
 
The pressure can not always be at 20-25% ... that is not a unit of measure. The gauge shows you psi.

If it is at 20psi when clean, then you would need to backwash again at 25psi which is 25% above 20psi.
 
What's the actual PSI reading when you start?

Depending on the age of your filter, the gauge could be bad and in need of replacement. You can buy cheap ones from the pool store that read +\- 1 psi or TFTestKits.net sells better ones that read +\- 0.5 psi




Sent from my iPhone using Tapatalk
 
jblizzle said:
If it is at 20psi when clean, then you would need to backwash again at 25psi which is 25% above 20psi.
Click to expand...

Thank you, this is what I needed to know. Being given a pool with no prior knowledge this is all stuff that blows over my head until explained.

As far as the slam goes at night I test the FC, I bring it up to 12 right after sunset and hope it's at 11 or less before sunrise. Is this correct?
 

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply