Clear pool, losing lots of chlorine

[msdodge]

Current:
FC 15.6 (tested first thing in morning)
CC .4
PH was low 7’s before SLAM
CYA was 40 before SLAM

I’ve been at SLAM levels for 8 days. before 8 days ago I was losing 4-5 pms per day so I started to SLAM (pool has always been clear).

First 4 days of SLAM at 16 gave me OCL of about 4-5 with little loss during the day.

I found a ton of algae behind my light and cleaned it on Sunday. I’ve brushed everyday and tried to keep slam at 20 since Sunday because I started losing a lot more chlorine.

I lose about 5ppm’s per night and lose about 10-15ppm’s per day since Sunday.

I don’t have much on my liner when I brush…a little bit (maybe a total of 3 tablespoons) of a copper color dirt on the bottom? Or copper color algae? The cover is broke so could be dust?

Would love some help thank you!!

 

[Texas Splash]

Losing 4-5 ppm overnight is quite a lot, so something is still eating that chlorine. Can you post some pics of your pool from different angles?

 

[msdodge]

We have quite a few wrinkles so I’m suspect of a leak but can’t find it.

 

[msdodge]

We have quite a few wrinkles so I’m suspect of a leak but can’t find it.

 

[msdodge]

The faded liner is from 3 years of bad pool service advice. We struggled with low ph and low chlorine levels all last year. This year I started TFP about a month ago after I wasted 10+ pucks a week because (now I know) the CYA was too high and never got a chlorine reading. I did an exchange of water and got my CYA from 170 down to 40.

 

[Texas Splash]

That is some pristine water and a very clean looking pool. There's not much else to check in that pool. You already discovered a mess behind the light, so the only other two places I can think of that might hide algae is under the drain cover and in the skimmer ara around/behind the weir door (the foam).

 

[msdodge]

That is some pristine water and a very clean looking pool. There's not much else to check in that pool. You already discovered a mess behind the light, so the only other two places I can think of that might hide algae is under the drain cover and in the skimmer ara around/behind the weir door (the foam).

How would you check the drain without scuba gear? Is there something we can pour in to kill it?
We don’t have weir doors…I did read we should. But I’m just trying to find a resting point with my chemicals after 3 years of frustration then I’ll check that out.

 

[Texas Splash]

How would you check the drain without scuba gear?

.... several times. Ha. There should be 3 or screws holding it down.

 

[Mdragger88]

Take all those floats out & leave them out- things like that get wet & stay wet, then grow stuff.
if u can - unzip them & check out the contents/ see if u can wash the covers in the washing machine or something.
I would submerge them in a tub of chlorinated water for a while separately at the very least.
Then see how u fare & If u pass your Overnight Chlorine Loss Test.

 

[mgtfp]

FC 15.6 (tested first thing in morning)
CC .4

Based on these results it looks like you are using a 25ml water sample for the FC test with 0.2ppm resolution. That must cost you a lot of reagent during a SLAM.

You can use a 10ml water sample, 1 drop of titrating reagent will then be 0.5ppm FC. Absolutely sufficient, especially during a SLAM.

The 25ml high precision FC test is really only required for pools that are managed without CYA (not recommended), where the target FC would be below 0.5ppm.

 

[PoolStored]

Do you have an autofill? If so, take a pic. Also, pics aren't exactly 360 degrees, do you have a ladder?

 

[msdodge]

Based on these results it looks like you are using a 25ml water sample for the FC test with 0.2ppm resolution. That must cost you a lot of reagent during a SLAM.

You can use a 10ml water sample, 1 drop of titrating reagent will then be 0.5ppm FC. Absolutely sufficient, especially during a SLAM.

The 25ml high precision FC test is really only required for pools that are managed without CYA (not recommended), where the target FC would be below 0.5ppm.

Thank you. I typically do but had accidentally started it at 25.

 

[msdodge]

Do you have an autofill? If so, take a pic. Also, pics aren't exactly 360 degrees, do you have a ladder?

No auto fill and no ladder. There’s no other objects in the pool. We did end up washing out the filter to see if that would help.

should i be trying to keep it at 16? It’s been very hot so I’m curious if it’s just the heat?

 

[Mdragger88]

should i be trying to keep it at 16? It’s been very hot so I’m curious if it’s just the heat?

Yes - if your cya is still 40ppm
Maintain Slam Level for your cya FC/CYA Levels until u pass ALL 3 end of slam criteria.
You are done when:

CC is 0.5 or lower;
You pass an Overnight Chlorine Loss Test
AND
the water is clear.
(Crystal Clear w/no algae dead or alive)
If u are losing fc overnight its from organics not heat.