Beautiful yellow walls....ugh

[meredd]

So I just purchased my first home and it came with a pool. 1 month before we moved in I went over and got all the proper gating and safety lines put in place. At that time I noticed sand in the bottom of the pool and what appeared to be staining on the walls. One month later we moved in. I swept and swept the pool, followed the previous owners instructions and finally got frustrated and went to the pool store. The installers helped me trouble shoot and the following weekend I had my filter fixed and sand replaced. My water was now cloudy and slightly green/teal. Afterr searching the net I found this wonderful site. I shocked the pool, vacuumed the dead algae out and watched the water turn crystal clear. Now I am stuck, I received my TF 100 test kit 2 nights ago and have started my first offical slam. The reason I have to slam is because the walls are yellow. I have scrubbed and scrubbed with the chlorine at shock level for what feels like 2 weeks. I have tried the vitamin c test and the chlorine puck test. Nothing is working. I can scrape it off with my finger nail or a magic eraser that's it. There are trees that line the fence. I keep finding what looks like sand in the bottom of the pool but disappears with a sweep of the vacuum. The yellow is lighter closer to the water line and gets deeper the further down the wall. I also have slight yellow on the bottom. I am convinced it is yellow algae.

My current numbers are
FC being maintained at 28 ppm
CC 1ppm
PH 7.2
TA 120
CYA 70 ( I need to redo this test just to double check)

I did lose chlorine over night but it was only 2ppm. I will continue maintaining current slam levels until I pass the OCLT then bump up to MA shock per the directions. Shouldn't I see some improvement in the wall color or am I being to hasty.

Any tips, advice, encouragement and wisdom are very welcomed. I am becoming slightly discouraged and I am wondering if I am doing something wrong.

 

[Texas Splash]

Hello again! I'm just thrilled you know so much about TFP stuff after being so new. That's great. So, let me cut & past some algae descriptors below for you to see if that helps:
Green algae usually floats in the water and turns the entire pool a murky green. Mustard algae is a yellow green color and grows on the walls and floor mostly on the shady side of the pool. Pollen and dirt tends to accumulate in drifts on the floor in places with slower circulation and can often look fairly similar to mustard algae. There are occasional exceptions to all of these rules, green algae sometimes grows in mats on the walls or floor, mustard algae sometimes floats in the water, etc. So positive identification isn't always easy. Mustard algae will spread and grow up the walls of the pool if you don't shock the pool. Dust/pollen will keep re-appearing, but will never accumulate on the walls of the pool. If you do shock the pool, mustard algae will mostly disappear as long as you are at shock level and brushing occasionally. Dust will continue appearing at the same rate when you are at shock level. Gritty is usually dirt; squishy is usually pollen; slimy is usually algae.

Sometimes a pic will help as well. If you've never posted a pic, you can upload your pics to Photobucket (free), then copy & paste the IMG code for that pic from Photobucket to your TFP post. Works great.

If it is Mustard Algae, the treatment is the same - SLAM first (regular), then once you pass all 3 SLAM criteria, increase your FC to the MA level at the bottom of the poolmath calculator for 24 hours.

I hope some of this helps.

 

[meredd]

I have yet to get in and pinch the dust. I will do that in the morning. The dust isn't on the walls only on the floor. It gathers in the center of the pool and directly across from the water jet blower. I have been keeping at shock level but am struggling with the cya test. I just re-ran it and got 80 this time. I have only used bleach so I am guessing the previous owner didn't know about TFP. I am trying to figure out the best way to drain some water without upsetting my new neighbors. We have had so much rain our yards are swamps as it is. I am at shock level and have been for a few days for sure, I think longer as I have done best guess work with the strips as I waited for my TF-100 and the yellow hasn't faded off the walls or ground. I noticed the bottom of the ladder has yellow in the creases as well, that also won't brush off. Any tips on getting more comfortable with the cya test, I would hate to unnecessarily drain water. I will post some pictures once the sun stops making the water sparkle.

 

[Texas Splash]

Here's a good review for CYA testing that may help you validate your reading: Proper lighting is important for the CYA test. You want to test for CYA outside on a sunny day, but keep the skinny view tube in the shade. Taylor recommends standing in the sun with your back to the sun and the view tube in the shade of your body. Use the mixing bottle to combine/mix the required amounts of pool water and R-0013 reagent, let sit for 30 seconds, then mix again. Then, while holding the skinny tube with the black dot at waist level, begin squirting the mixed solution into the skinny tube. Watch the black dot until it completely disappears. Once it disappears, record the CYA reading. After the first test, you can pour the mixed solution from the skinny view tube back to the mixing bottle, shake, and do the same test a second, third, or fourth time to instill consistency in your technique, become more comfortable with the testing, and validate the CYA reading.

- - - Updated - - -

It's always possible the particles on the bottom (which appear to be like sand) may be different form the staining you see on the walls. Let's see how your CYA test turns-out, and possibly another OLCT to see if continuing the SLAM is still warranted.

By the way, I don't suppose you know when the last time that sand filter was cleaned/backwashed huh? Previous owners leave any paperwork history for you? (DISREGARD this question. I see above)

- - - Updated - - -

You should have a gauge on the filter. Curious to know if the previous owners marked a "clean" and "dirty" line on the gauge to indicate when it would be time to clean the filter. Just looking at any possibilities. DISREGARD this for now as well.

 

[Texas Splash]

Sorry - disregard my question about the filter. I re-read your post.

- - - Updated - - -

So the two other things that come to mind as I read your pool symptoms:
1 - Even though you've "shocked" before, you've only been able to accurately SLAM (via TFP) for two days with accurate readings (TF-100) - correct?
2 - Following filter maintenance, there is always a slim chance something didn't' get put back together exactly as before, allowing some sand to get released back to the water and settle on the bottom of the pool. But I don't want to assume that quite yet. It's always possible the "dust" you are seeing is dead algae - which is a good thing.

For right now, I would be more inclined to keep the SLAM FC level until you pass the 3 SLAM criteria, and re-evaluate everything from that point.

 

[zea3]

Do you have a test result for Calcium?