Clear, but no chlorine???

[mary jo]

Hi Big Dave- THANK YOU for an explanation that makes sense. The only caveat is that ( and I'm being honest here) I forgot about the mineral sanitizer until I looked through my pool papers, so I have not ever changed the cartridge in 2 1/2 seasons of use. So I wonder if it's still doing anything.

Staining wouldn't be good, but I wondered if I could do a stain test while adding the bleach at intervals. I'm assuming you don't add 6 jugs at once?
Oh- last night at around 10:00 I went ahead and did add 1 jug of bleach, very very slowly to see what would happen. 2 hours later I tested the water, then closed the cover.

Last nights results (around midnight): FC=3.5. CC=1.0
This morning I opens the pool around 10:00 and tested again: FC=1.0. CC=.5

I will start my test bucket, and wait for more info on how much bleach to add.
Thank you !!!

[BigDave]

I'm glad to hear that the "mineral" cartridge hasn't been replaced - those things kinda make me angry because they're sold on false promises.

Do the bucket test and let us know what you find in it.

Do be sure to keep chlorine in the pool - it will be much harder to clean up a full fledged algae bloom.

[mary jo]

Good Morning! I just checked the bucket of test water and the bucket is white- no staining at all. I added 1 jug of bleach to my pool yesterday morning, and 1 last evening and this morning the FC=0, CC=1, pH=7.2
What do you suggest now?

[BigDave]

I recommend that you bring the FC to shock level. At CYA 150ppm, 20% shock level is 30ppm FC. In 26K gallons it'll take 10 jugs (not jubs ) of 8.25% to get there from FC 0ppm. All at once. Pour the bleach around the pool so it's not concentrated in one place.

Keep the filter running 24/7. Keep FC at 30ppm until you lose less than 1 ppm FC overnight, you have 0 or nearly 0 CC and the pool is clear. Run the pump 24x7 while shocking. Leave the pool cover open if you can - some of the byproducts produced while shocking the pool may damage the cover.

[mary jo]

OK- bought 12 jugs of bleach this morning. I have 15,000 gallon pool. Should I wait until tonight (after sundown)? Also- how exactly do I test for FC of 30- dilute a pool water sample like I did for the CYA test?

[BigDave]

I just re-read about the Tuesday pool party - perhaps you should wait until after the party to shock. In that case, pour 5 jugs 8.25% and be ready to add more. Test FC/CC twice daily (early morning and evening). Add bleach as needed to keep FC at 15. If it drops below 8, test / dose more often. FYI each jug of 8.25% bleach will add about 3ppm FC to your pool.

Don't add any more tabs to chlorinator.

I just noticed that you pH is a little low - Add a box of Borax (20-Mule Team - laundry aid). You won't get accurate pH readings while FC > 10.

Keep us posted.

P.S. Why do you cover the pool at night?

[BigDave]

OOPS! I thought you said pool was 26K gallons - 15K is different.
I'll post again in a minute.

[FormerBromineUser]

BigDave: while you're calculating, is there any additional issue with her CH being so high (750)?

[BigDave]

OK. So...
To start shock, add 6 jugs 8.25% bleach to go from 0 FC to 30ppm FC.
or
To get through party first, add 3 jugs 8.25% bleach to go from 0 to 15ppm FC.

Each Jug will add a little over 5ppm FC.

I would add a half box of Borax.

Also:
Sorry about that! Your first post said "15,000 SF rectangular" then I scanned for a volume and, apparently, found FormerBromineUser's volume - My Bad.