Algae in Pebble Pool Question

[Starplex]

Our pool has Wet Edge Satin Matrix in the Northshore Carribbean color. The pebble contains a moderate amount of black pebbles as well as tan and blue. I have seen smooth white plaster pools with algae before, but never a pebble pool. Isn't if very difficult to see the algae with so many pebble colors? I am concerned as my FC fell to around 1.5 today when I tested and then after running the Polaris 9300 robot I had streaks on the walls where you could easily see where he had scrubbed. Looked like the plaster was brighter blue where the robot had cleaned. I then went around the pool with the nylon brush and brushed the sides. However, even by brushing very hard I could not make the plaster bright like the robot did (in the dull areas). I have heard that the walls may feel slimy if algae is present. The walls are not slimy feeling at all. Also the CC is 0. If algae were present wouldn't you expect to see CC higher than 0?

I just want to know exactly what to look for just in case the culprit was to appear now or in the future.

On another topic my robot still pulls out small pebbles when cleaning. Not near as many as in the first couple of months after pool build. The pool was finished & opened in August of last year, (9 months old). Is this normal?? I emptied about 1/2 teaspoon of pebbles out of the robot filter today. CH = 270
Thanks

 

[duraleigh]

I just want to know exactly what to look for just in case the culprit was to appear now or in the future.

A prime principle of BBB is accurate testing. Testing for FC will reveal the potential for algae long before you can see it. If your tests results are kept within the guidelines established, the chances of you having algae are remote.

 

[JasonLion]

Getting some extra pebbles coming off your first spring is normal. If they continue to come off at that rate there might be some problem.

CC is often zero throughout an algae bloom, though it can also be above zero.

 

[Starplex]

Thanks Jason!! I do intend on doing proper testing and keeping the levels where required. However, we do get some monster rains from time to time in SE Texas & if I'm away for the weekend when this occurs the FC can disapate rather quickly. Just wanted to know how people often figured out a small algae problem may be brewing after a short stent with low FC.

 

[Bama Rambler]

The easiest way to tell if you have something going on is if you notice an increase in daily FC loss over a couple of days. If you manually chlorinate the pool this is easy because you'll notice the FC is lower than normal when testing and t takes a greater amout of chlorine to bring it back to normal. If using a swcg you'll notice it because you'll have to increase the runtime or output of the unit to maintain the same FC.