Algea or filter problem? New pool owner

[Hawkeye80]

1st off thanks to everyone on this board. My wife told me I was seeing more of the girl at the pool store than her...and she was right! 1st a little background. Purchase a home with an in-ground pool last winter and opened it about 5 weeks ago. My 1st time owning a pool. I found this board last week and have since purchased a Taylor k-2006 test kit and have adopted the BBB method. I have had a recurring problem with debris in the bottom of the pool. It always reoccurs in the same spots. In the shallow end where there are some slight recesses in the vinyl, along the ridge where the shallow end begins to slope down, and around the main drain. It seems to "grow" mainly when the filter is running. To me it LOOKS like algea although it doesn't feel slimy. It poofs up when brushed and doesn't really stain (other than when it sat for a few days but the stains were removed with only light to moderate brushing). I vacuumed to waste several times but got sick of all the water loss. When I vacuumed normally, afterwards the water coming out of my returns was discolored. I passed the OCLT this morning (went from 3.6 to 3.4). Can passing this test rule out algea and point me to a potential problem with my filter? I've been spending exponentially more time working on my pool than in it!
Current levels:
FC:3.4
CC:.4
CYA:70 (the pool store reading was 15! I HAD been trying to work it up)
Ph: 7.4
Alk: 110
Cal.:170
Thanks in advance! I was overwhelmed with the whole process and was lost until I found this site.

 

[Hawkeye80]

One more piece of info... I have added DE and backwashed. Did not seem to make a difference.

 

[Butterfly]

Welcome to TFP

What jumps out to me is the lack of chlorine in your pool! With a CYA of 70, FC should be maintained between 5 and 10, and never below 5!

How does the water look?

You may need to do a deep cleaning on the sand filter. How-to article in Pool School.

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Did you do the SLAM process, or just an OCLT?

 

[Richard320]

Those aquatic dust bunnies are algae carcasses. Take the FC up to 10 or 12 when you dose and I'll bet things improve over the weekend.

 

[Hawkeye80]

Thanks for the advice. The water looks perfect. I did not SLAM yet. i was using the oclt to try to determine if it was needed. A deep cleaning of the filter is now on my to do list. I will raise the chlorine levels up. Are levels of 5-10 ppm safe to swim in then I assume? The info that the previous owner left behind for me recommended a range of 1-3. I'll be sleeping on the couch if my wife gets out of the pool with bleached hair!

 

[Butterfly]

Thanks for the advice. The water looks perfect. I did not SLAM yet. i was using the oclt to try to determine if it was needed. A deep cleaning of the filter is now on my to do list. I will raise the chlorine levels up. Are levels of 5-10 ppm safe to swim in then I assume? The info that the previous owner left behind for me recommended a range of 1-3. I'll be sleeping on the couch if my wife gets out of the pool with bleached hair!

Yes, it is safe. Not only safe, but necessary to keep the pool sanitized with that CYA level. See the Chlorine/CYA chart in Pool School or the PoolMath calculator button on the top menu bar.

 

[Hawkeye80]

Perfect. I just added bleach to bring my level up to 8ppm as per the chart. The PoolMath calc is pretty much the coolest thing ever. Just like the chart the pool store would give me but better since now I actually have accurate test results!