CYA, dirt clods, and free chlorine

Nillawafers

Member
May 24, 2019
11
San Gabriel, CA
About 3 weeks ago my 3 year old threw 3 dirt clods in our above ground vinyl pool (14’x42”). I immediately shocked and vacuumed, but it seemed since my dirt is VERY fine, the filter (a cartridge) wasn’t catching it all. I would have a layer of dirt on the bottom even after running the filter 24/7. I did some research on here and bought a 5 micron “slime bag” and attached it to my return. This seemed to work (mostly) but I’ve still been getting a bit of sediment collecting on the bottom.

In addition to this I tested yesterday and everything was within my parameters. I added about 3 cups of 6% bleach tested before my boys swam all afternoon but this afternoon I tested and it’s pretty much GONE. My combined chlorine is now 1.5 so I’m shocking it. it’s been really hot here, so I tested my CYA and it was at 30, which is at the bottom of the guidelines?

When I first started out with this pool (it’s my first) I miscalculated and added too much CYA so for a while the pool has been sitting at 60. I tested it last week and it was 60 still so either I didn’t test right (I guess it has to be in sunlight ect ect) or I lost a bunch in a week. This is possible because in the process of jury rigging my return to take the slime bag I lost a bit of water (like maybe more than a bit haha). I just read that people in super hot areas (I live in LA) like to keep their CYA high - is there truly a difference?

So I guess what I’m asking is should I be adding more CYA? I’m obviously shocking my pool right now, and I will be doing an overnight test. Should I add the cya before I shock or after? E1D01D9B-8F62-486C-A32A-42901B75C7C5.jpeg
Slime bag jury rigged on the side, catching tons of dirt.
 

Nillawafers

Member
May 24, 2019
11
San Gabriel, CA
I don’t think the app updated, I just tested it 30 minutes ago and it was between 30 and 40.

I have read all of pool school, and am definitely glad I found it!

I am using a Taylor FAS/DPD kit.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
21,333
Laughlin, NV
Great. Leave your CYA as is. 40 ppm is perfect for your area.

Good job on the test kit. If you can fill out your signature, really helps us help you. Include the test kit description in your signature.
 

Nillawafers

Member
May 24, 2019
11
San Gabriel, CA
Ok. So me being me, I figured I would test again after I added some water (kids were splashing a lot) before I shocked. Before when I tested the first time I had the filter going but the bag was on, and it doesn’t really circulate super well with the bag, so I took it off and let it run for about 30 while I added some water.

Tested the water from deeper in the pool (more like halfway down as opposed to the top) and now it says FC is at 1.5 and CC is .5. Do I truly need to shock?

I should also retest CYA since I added water yes? Thanks!
 

Nillawafers

Member
May 24, 2019
11
San Gabriel, CA
Just an update. After bumping it up to 10, I forgot to do an overnight test (cus zzz), but I didn’t treat it at all today (have an giant test coming up) and when I finally got home to test it, it was at a 1.5 FC again and 1 CC. I started the SLAM process tonight and set my alarm.

After the filter ran this morning I had more brown sediment on the bottom which I can only assume is dead algae that is not being caught by the filter, or falling onto the bottom. I am assuming the first because I can vacuum to my hearts content but if the filter is on, insidious piles of algae will miraculously appear.

Is there anything I can do besides a slime bag for the dead algae? The slime bag is a pain to rig onto the return.

My pool was pretty perfect before giant amounts of dirt was thrown in it :(
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
21,333
Laughlin, NV
Your filter should capture the sediment. I suspect you are just not getting to the filter. Brushing and vac is the best way.
 

Nillawafers

Member
May 24, 2019
11
San Gabriel, CA
Day 2, didn't pass overnight, definitely algae, definitely continuing SLAM.

I'm assuming it's normal for CC to climb as FC kills off algae and contaminants?

I'm running out of FAS/DPD titrating reagent and Amazon is on back order....does anyone know where to get this stuff in person in Los Angeles?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
21,333
Laughlin, NV
For FC testing, use a 5 ml sample. One scoop of powder and each drop of reagent is 1 ppm FC. Only do this during SLAM process.