What is this and what should I do ?

[aswetich]

Opened my pool the other day and used robotic cleaner to get the little amount of debris that was in to. The bottom was spotless after the cleaner was done. The water wasn't crystal clear just cloudy.
FC 4.5
CC 0
PH 7.2
CYA 70

I got deal on some HTC 10% chlorine last year so I added 3 gallons yesterday to shock it assuming it would be weak from storage. I have been running the filter 24x7 for about 36 hours.

This morning the pool has patches of light brownish/green dusty patches. I fought with this all last summer thinking it was pollen or something but the air and water temp is 50 degree now with no pollen.

Here is a link to pictures:
http://s1128.photobucket.com/user/aswetich/library/


Todays free chlorine was 12

 

[Charlie_R]

If you still have 0 - 0.5 CC, chances are high ha it is nothing more than airborne dust getting into your pool. You don't say what kind of filter you have. I will assume sand or DE. What color is the water in your backwash? Brown or green?

 

[duraleigh]

If that was my pool I would SLAM it. You didn't put in enough chlorine to get to SLAM values and you didn't hold it there until your pool was crystal clear.

Despite the cold temps, I think what you see on the bottom of the pool is dead algae.

A complete SLAM will eliminate that but you must follow it through by following the SLAM directions to the letter.......you cannot let your FC dip below 28 ppm.

I imagine your pool will stay clear all swim season if you do this now.

 

[JamesW]

I agree with duraleigh, it's probably algae, possibly mustard.

If you can vacuum through the skimmer with a skimmer sock, or knee-hi stocking in the basket, you can see if it gets caught in the sock. Dirt will usually get caught and mustard algae will usually go through.

 

[Richard320]

snip
This morning the pool has patches of light brownish/green dusty patches. I fought with this all last summer thinking it was pollen or something but the air and water temp is 50 degree now with no pollen. snip

If that stuff looks like the dustbunnies under the bed, and they disintegrate into nothingness as soon as you even try to brush them, that's dead algae settling out in drifts.

SLAM it and be vigilant about maintaining FC appropriate for your CYA level for the rest of the season and you'll never see it again.

 

[aswetich]

Slamming the pool tonight

I just added enough bleach to get my FC to the slam level tonight. Since I am running my filter 24x7 I also set my Aquapure to 10% to help maintain the level. I will check 1st thing in the morning and in the afternoon when I get out of work. Thanks !