Algae Entering Through Pool Lights?

[SusW4]

Good morning! First time poster here. I am grateful for finding this website and have saved a lot of money by using the SLAM method to open our pool.
While our pool water is clear, there is algae growing in the grout of a small area of the water-level tiles. Also, even though they are no longer connected (we took the fiber optic box out a few years ago when redoing the pool deck), there is visible algae growing under the 2 pool lights. I believe that has been causing algae to continue to be introduced into my water. I just can’t seem to get to a point of not adding liquid chlorine on an almost daily basis. (We connected our SWG last night and added salt to the water to get the levels needed for it to generate chlorine. I found out my dear hubby left the SWG on 20% overnight so that’s probably why my Fcl was the same as my test from last night which has not been happening. )
Here are my most recent test numbers (Taylor K-2006 Test kit):
Fcl 13
Ccl .5 (definitely pinker this morning than last night)
TA 90
CH 210
CYA 50
Salt 2870 (Aquachek strips)

(I didn’t bother to test the Ph because of the high Fcl but it was at 7.0 nine days ago which was the last time the Fcl was below 10 and I started the SLAM.)
I am adding 2.5 lbs. of CYA using the hose method now. And I put a gallon of 10% liquid chlorine in since I see the algae is growing.

Does anyone have a way to resolve the algae that continues to grow under the light covers? After reading this long post, any suggestions would be most appreciated. Thank you. Sus

 

[Divin Dave]

Hi Sus,
Chances are, there is a lot of algae behind the pool light. We see that quite often. If possible you need to remove the light from the niche to make sure and clean out any algae back there.

Part of regular pool maintenance is to periodically brush the walls. TFP method doesnt make that part of maintenance go away.

Part of the slam instructions are also to brush the walls daily during the SLAM. If you do that, Im pretty sure it will resolve this issue.

 

[SusW4]

Thank you for your quick response! I have been brushing the pool at least twice a day and we are running our automatic pool cleaner every 2 days. Our water has been clear for a week.
Do you have a good resource that I can pass on to my husband so he can clean out the niches?

 

[arielpool]

I usually get an old toothbrush and simply go in there until it's clean. Use a snorkel and a mask.