1st time SLAMer help please....

[AguiarHouse]

Hi! First time SLAMing and I don't think its working. The FC seems to be dropping more overnight and the effectiveness of the bleach seems to be less as well. Water is still clear with maybe a couple very faint algae spots only but won't hold chlorine. Any advice?

Pool: 20,000 gallons, in-ground, plaster, water temperature is 82

Pre-SLAM test numbers (using Taylor K-2006):
Water: Clear but some algae (green patches and brown spots)
FC: 0
pH: 8 (we added muriatic acid to get it around 7.6 right before starting SLAM)
Alk: 130 ppm
Calcium: 240 ppm
CYA: 20-30 ...this was 90+ last summer but we had a bad leak and have added a ton of fresh water (and switched to bleach, thank you TFP) so it lowered significantly. I'm scared to get it too high again but should we add some liquid stabilizer or get some shock bags with dichlor?

Normally we use liquid bleach as needed (about a gallon a week), 2 floating tabs with trichlor consistantly, and muriatic acid as needed for pH.




SLAM process results:

5/18:
12pm - Added 4 gallons liquid bleach
2pm - FC 3.6, added 2 more gallons
5pm - FC 4, added 2 more gallons
7pm - added 4 more gallons
10pm - FC 12

5/19:
7am - FC 10, CC 1
1 pm - FC 6, added 2 gallons
4 pm - added 2 gallons
8 pm - FC 5.5, added 4 gallons
10 pm - FC 13

5/20:
9 am - FC 9, added 2 gallons
5 pm - FC 5, added 4 gallons
9 pm - FC 9

5/21:
8 am - FC 6
2 pm - added 2 gallons

Thank you for the help!

 

[Mendy48]

It looks like you are doing everything right. Once algae is being killed off, the chlorine will not deplete as fast as it used to. Continue SLAMing...It may take some time...

Are you still using 2 floating tabs with trichlor consistently?

I see that your losing about 2-4FC if you were to do the Overnight FC Loss Test (OCLT). Keep SLAMing... it takes a little P.O.P to do this...

Looking at your dates:


10pm - FC 12
7am - FC 10
FC Loss: 2

10 pm - FC 13
9 am - FC 9
FC Loss = 4

9 pm - FC 9
8 am - FC 6
FC Loss = 3

You have to keep SLAMiing until you pass the Overnight FC Loss Test (OCLT)

 

[kellyfair]

What percentage bleach are you using, and what are you using for pool volume? In text you say 20,000 gallons, but in sig you say 19,000.

 

[AguiarHouse]

It looks like you are doing everything right. Once algae is being killed off, the chlorine will not deplete as fast as it used to. Continue SLAMing...It may take some time...

Are you still using 2 floating tabs with trichlor consistently?

I see that your losing about 2-4FC if you were to do the Overnight FC Loss Test (OCLT). Keep SLAMing... it takes a little P.O.P to do this...

Looking at your dates:


10pm - FC 12
7am - FC 10
FC Loss: 2

10 pm - FC 13
9 am - FC 9
FC Loss = 4

9 pm - FC 9
8 am - FC 6
FC Loss = 3

You have to keep SLAMiing until you pass the Overnight FC Loss Test (OCLT)

Yes, I am still using the tabs with trichlor...should I stop? I think that I need to increase the CYA a little since its currently under 30...what is the best way that I do this? Is there still be algae if I don't see any and the water was clear with only minor spots before starting? Seems odd that there would be that much algae to be eating up that much chlorine. What does P.O.P. stand for?

 

[kellyfair]

POP is Pool Owner Patience!

I personally would just use liquid chlorine for your present CYA level to do the SLAM, so you can predict what your additions should give you. You can always use the tabs to bump CYA after SLAM is complete.

 

[AguiarHouse]

What percentage bleach are you using, and what are you using for pool volume? In text you say 20,000 gallons, but in sig you say 19,000.

I am using 8.25% bleach (Target Up&Up brand low-splash concentrated for $3/gallon). I wasn't able to find stronger. Do you have a recommendation for where I can find a higher concentrate?
I don't know the exact volume because the pool is oddly shaped and we recently purchased the home without any pool details from the previous owners. I'm using 20,000 as a rough estimate.

 

[mknauss]

The issue with using tabs to increase CYA is it is slow. With the sun impacting your pool you really need a solid 30 to 40 CYA to protect your FC.

Check any lights, main drain covers, weir doors, etc to be sure there is no Algae hiding in them.

POP is Pool Owner Patience. It is pretty typical to have 'clear' water and not be able to pass a Overnight Chlorine Loss Test. Part of it is a new convert to TFP has never really seen clear water.

Take care.

I just saw you are using 'low-splash' bleach. Discontinue using that. It is adding surfactants/polymers. Use plain bleach or liquid chlorine.

 

[kellyfair]

Ok. If you find your chlorine additions are making FC higher than expected, you may want to bump volume down a bit.

You can actually get a higher concentration of LC at pool stores, and they have reusable containers too, which is nice for cutting down on your plastic garbage. Just don’t let them sell you anything else!

 

[Mendy48]

In my experience, I just use a stabilizer (granular) to increase my CYA to about 30 or 40. I'll recommend you do this. Put the granular in a socks once you get your actual stabilizer. Once in the socks, hang the sock near the return jet and wait 24-48 hours to dissolve. You can also massage the hanging socks (with the stabilizer). It sometimes speeds up the process. Is your CYA 20? You should increase it to 30. Use PoolMath to get the actual oz you need to increase your CYA. Also, there could be algae you don't see for sure... Your just have to practice Pool Owner Patience (P.O.P). Your pool may be clear, and your CC may be 0.5, but it looks like you still haven't passed the Overnight FC Loss Test (OCLT). You have to pass this test to complete your SLAM. Keep SLAMiing...make sure to maintain your shock level...give it time...You are on the right track.

Yes, I am still using the tabs with trichlor...should I stop? I think that I need to increase the CYA a little since its currently under 30...what is the best way that I do this? Is there still be algae if I don't see any and the water was clear with only minor spots before starting? Seems odd that there would be that much algae to be eating up that much chlorine. What does P.O.P. stand for?