Black Algae embarrassed

[Katodude]

So here I was thinking I am a good TFP disciple following all the guidelines. I dont know if it was the crazy rain (more than 10”) that cause my FC to drop or it lowered my CYA. That coupled with a lack of brushing in certain spots (the corner) I got some spots of black algae. I picked some pieces out smeared them and it was green. Maybe about a dozen spots. I am embarrassed this should not happen to me. I admit I am not a great brusher and depend on the robot too much.

Anyway got aggressive. Took a mask and snorkel, a wire brush, and a little bamboo skewer and went at it. Pretty sure I scraped and picked at every spot completely clean. Then took a 1” PVC tube a funnel and tried to pour 10% bleach on all the spots. Got pretty close to covering all of them and the yellow color of the bleach helped make identify that they flowed over the spots, if only for a few seconds. The kept the pool at SLAM levels for the last two days. Did an OCLT and passed, pool is spotless. Cleaned out the filter, running the robot with fine pleated filters in ultra clean mode.

Took the mask out again and inspected the whole pool, no spots. Scrubbed the places with the wire brush again for good measure.

I plan on using the PVC pipe again to super does those areas again and keep the pool just below SLAM level for at least a week, and a few ppm about ideal level for a while after.

Will also be more diligent about brushing and make sure I keep my FC on the high level from now on.

Anything else I should do? I really want the nuclear option. I never want to see those spots again.

 

[mknauss]

Black Algae

This guide provides a step by step procedure for eliminating black algae in your concrete or gunite pool. Read full post here.

www.troublefreepool.com

Maintain a higher base FC level for several weeks. Keep disturbing those areas with brush, etc.

 

[cowboycasey]

I think you have covered the nuke option Our pools are living beings and they change, TFP has taught you to see the change in your pool and how to take care of it.. Great job

 

[Katodude]

Well it is one week later. I have hit the areas with the stainless steel brush almost every day. Other days I used the regular nylon brush on the pole. Did a full visual inspection with the mask and it is looking pretty good. Been running FC hot. At least 12 and up as high as 20, for my CYA of 60. SWG has been off since I bought a bunch of LC that I am storing outside and has a limited shelf life. Also been dumping the LC straight over the place where the spots used to be and it seems to wash down over the areas since it is slightly heavier than the water.

Going to bump my CYA to 70 today, but keep the FC hot for at least another week before I turn on my SWG again. I want to make sure those spots are DEAD, DEAD, DEAD!!!

Am I missing anything? I have not done an OCLT in a week, it might be worth doing one in the next couple of days.