2nd Day At Shock Levels, Still Brushing up Algae from the same spot (stairs)

[SW Pool Owner]

I have a 3ft->5ft->8feet pool, and I've always had an issue with algae in the 3ft area on the stairs. Whenever I brush the stairs I see algae flying up. When I brush the floor of the 3ft there's less, but I still see algae being brushed up.

This has happened everytime I've done SLAM. This is my 3rd time SLAMing and I'm always brushing up algae from the stairs, even though my FC is at 22 with a CYA of 40-50. This algae grows back and clouds up my water afterwards and I have to repeat the SLAM process again.

Is algae on the stairs expected, and am I supposed to brush everyday and just deal with the spores?

 

[mknauss]

As shown in Why is my pool so cloudy? All chemistry levels in check, it seems you struggle to keep your pool algae free. It should not be that way if you follow the Recommended Levels.

How do you chlorinate on a daily basis?

 

[SW Pool Owner]

I use an SWG, never letting my FC run below 7. I've kept my FC on the higher end for weeks now, CYA at 40-50.

 

[mknauss]

Then either you have severely poor circulation or the test data is incorrect. The low CYA for a SWCG could be part of the issue. Chemically, what you present is not possible.

 

[SW Pool Owner]

Considering the algae starts in the same 1/3rd of the pool every time, what would a sign of poor circulation be? The deeper ends (5ft and 8ft) never have algae brushed up at first, until I notice a lot of algae being brushed up from the 3ft area, and then when I brush the deeper bits I will see a little algae being brushed up

I have 1 jet of water in this area pointing directly across at a skimmer, it seems to pump water fine, it just does not keep the stairs and floor algae free

 

[mknauss]

Does the pool get brushed a couple times a week? Swam in often? Any kind of cleaner used?

 

[SW Pool Owner]

I haven't swam in the pool in days, no cleaner used, does it get brushed a couple times a week ehh.... I have a robot vacuum cleaner that I run every other day or so. I try to brush a little on weekdays and do a more thorough brush once a week on the weekend. I probably neglect brushing a little, but brush at least 1 - 2 times a week

 

[mknauss]

That the issue happens in a shallow area implies the FC falls below minimum in that area.

 

[Bperry]

Might be good to take the water test samples from the shallow area.

 

[SW Pool Owner]

Good point, will try that

 

[Mdragger88]

I have a 3ft->5ft->8feet pool, and I've always had an issue with algae in the 3ft area on the stairs. Whenever I brush the stairs I see algae flying up. When I brush the floor of the 3ft there's less, but I still see algae being brushed up.

This has happened everytime I've done SLAM. This is my 3rd time SLAMing and I'm always brushing up algae from the stairs, even though my FC is at 22 with a CYA of 40-50. This algae grows back and clouds up my water afterwards and I have to repeat the SLAM process again.

Is algae on the stairs expected, and am I supposed to brush everyday and just deal with the spores?

The SLAM Process is not complete until u pass ALL 3 end of slam criteria
You are done when:

CC is 0.5 or lower;
You pass an Overnight Chlorine Loss Test
AND
the water is clear.
(Crystal Clear w/no algae dead or alive)

*Check & scrub every nook & cranny where algae may hide (light niches, drain covers, ladder handrails, skimmer throats/weirs, etc.)
*Run slam level water through all water features & lines for at least a couple hours a day during the SLAM Process.
*Brush & or vac daily (this breaks up biofilms that algae uses to protect itself from chlorine)
*Backwash/clean filter when pressure rises 25%over clean pressure.

I suspect you ended slam too early in the past. Or as @mknauss mentioned there is an area with poor circulation that has a lower fc once u return to maintenance fc levels.

 

[SW Pool Owner]

So day 4 now, still brushing up dried green powder from the sloping edges / corners of the pool and a tiny bit of green dust from the shallow floor of the pool. Chlorine in shallow part is consistent with deep end. I'm assuming it's dead algae and not Calcium hypochlorite that didn't dissolve properly. Hopefully overnight chlorine loss stabilizes soon..

 

[Mdragger88]

If it’s green it’s not dead
If your cya is between 40 & 50 you count it as 50 & slam level is 20ppm.

 

[SW Pool Owner]

I've been measuring FC in the morning and it's gone from 15-16-17-18 (today) so 1ppm per day progress. I just throw in 3 - 4 bags of calcium shock in there, since each bag only raises the ppm by 2ppm or so. I forgot to run the pool timer 24/7 as we reduced the timer to investigate high energy usage (turns out our central AC is killing our pockets), but just changed that now. Also adjusted the first valve to point at the stairs instead of straight towards the skimmer.

Hopefully 19 ppm FC tomorrow morning

 

[Bperry]

I've been measuring FC in the morning and it's gone from 15-16-17-18 (today) so 1ppm per day progress. I just throw in 3 - 4 bags of calcium shock in there, since each bag only raises the ppm by 2ppm or so. I forgot to run the pool timer 24/7 as we reduced the timer to investigate high energy usage (turns out our central AC is killing our pockets), but just changed that now. Also adjusted the first valve to point at the stairs instead of straight towards the skimmer.

Hopefully 19 ppm FC tomorrow morning

You would be wise to switch to liquid chlorine that calcium is going to build up and draining water is the only way to get rid of it.

 

[duraleigh]

I am not in favor of sampling in one area of the pool expecting the results in that area to be different. They NEVER should .

Pools managed correctly have even distribution of pool water and you should be able to produce identical test results from any spot (within reason)

 

[SW Pool Owner]

You would be wise to switch to liquid chlorine that calcium is going to build up and draining water is the only way to get rid of it.

(Un)lucky for me I have a small leak in my waterfall and my CH levels dropped quite a bit, and I'm constantly refilling 2-3 hours through a hose of water once a week. So for now I should be ok and am significantly below recommended CH levels. Plus the liquid chlorine is really heavy and it takes lots of bottles to get my pool to shock level, so I'm hoping to get by for now until this algae is gone.

It sucks my pool is pretty clear but I'm still finding dead algae being brushed up every few hours. I just brushed again now ~5 hours later and found more dried granules in the corners.

I realized I hadn't cleared my vacuum in a bit and emptied quite a significant amount of gunk from that, maybe that was potentially chewing through some of the FC?

 

[SW Pool Owner]

I am not in favor of sampling in one area of the pool expecting the results in that area to be different. They NEVER should .

Pools managed correctly have even distribution of pool water and you should be able to produce identical test results from any spot (within reason)

Make sense, in my case because there is significantly more algae being brushed up in the shallow area, it was worth to check if circulation was a problem I guess.

 

[SW Pool Owner]

Actually, I'm out of powdered shock and I've gone ahead and cancelled my pending Amazon order. Using the pool math calculator 4 gallons of liquid shock should be raising my FC by 14, which seems a better value than what I'm getting with these powdered bags, so I will try the liquid chlorine again.

 

[Mdragger88]

Do your best to Maintain slam level- multiple times per day is best. The more often u test & replenish the faster things go.