HI all – long time subscriber here and haven’t posted in awhile but still love reading the forum.
Couldn’t get bleach this year so ended up buying 20 gallons of liquid pool shock at Leslies, which is supposed to be 12.5%. I test daily for Cl and add what is necessary to get to target level for my pool’s CYA. I calibrated the pitcher I use to add bleach (using pool calc) for the 12.5%. Well, I think the Leslies stuff has only been giving me half the strength. I should have figured this out sooner. So, for the first time in years, I think I’ve been under chlorinating. And, I have algae now. Maybe 2 or 3 times over the years, I’ve had issues that I think may be mustard algae where the pool floor collects what looks like dirt and easily brushes away. I have that currently, but I also have patches of slimy film on parts of the walls (not the floor). I’m a bit colorblind so can’t tell if they are green/yellow/brown. The water clarity has been fine – it is not cloudy.
Started a SLAM yesterday around 630P. Before the slam, I brushed the walls to get rid of the spots with the film. Alkalinity was 80, CYA slightly over 50, and Ph slightly over 7.2. Got Cl up to mustard algae levels of 32. I did this in 2 waves, one hour apart. After adding the shock for the first wave, the water remained clear, but after adding the 2nd wave, the water become very dull looking, I wouldn’t say cloudy, but definitely not as clear.
This morning at 645A (very cloudy weather), Cl was 21. I was very surprised at how much Cl was lost overnight. I am doing each Cl test twice so I know the readings should be good. Water was clear. I didn’t go in, but felt around the areas that had the slime and they seemed ok. But, I did notice one 6” slime patch on the wall which I brushed away. I added Cl to bring me back to 32 and brushed, so I’m continuing the SLAM process. I don’t know if I have mustard algae, or not, so I’m treating like I do by using the higher Cl levels. Running pump 24/7 and using skimmer/main drain for circulation. But, here are my questions (any other feedback most welcome on the other details, too)
Couldn’t get bleach this year so ended up buying 20 gallons of liquid pool shock at Leslies, which is supposed to be 12.5%. I test daily for Cl and add what is necessary to get to target level for my pool’s CYA. I calibrated the pitcher I use to add bleach (using pool calc) for the 12.5%. Well, I think the Leslies stuff has only been giving me half the strength. I should have figured this out sooner. So, for the first time in years, I think I’ve been under chlorinating. And, I have algae now. Maybe 2 or 3 times over the years, I’ve had issues that I think may be mustard algae where the pool floor collects what looks like dirt and easily brushes away. I have that currently, but I also have patches of slimy film on parts of the walls (not the floor). I’m a bit colorblind so can’t tell if they are green/yellow/brown. The water clarity has been fine – it is not cloudy.
Started a SLAM yesterday around 630P. Before the slam, I brushed the walls to get rid of the spots with the film. Alkalinity was 80, CYA slightly over 50, and Ph slightly over 7.2. Got Cl up to mustard algae levels of 32. I did this in 2 waves, one hour apart. After adding the shock for the first wave, the water remained clear, but after adding the 2nd wave, the water become very dull looking, I wouldn’t say cloudy, but definitely not as clear.
This morning at 645A (very cloudy weather), Cl was 21. I was very surprised at how much Cl was lost overnight. I am doing each Cl test twice so I know the readings should be good. Water was clear. I didn’t go in, but felt around the areas that had the slime and they seemed ok. But, I did notice one 6” slime patch on the wall which I brushed away. I added Cl to bring me back to 32 and brushed, so I’m continuing the SLAM process. I don’t know if I have mustard algae, or not, so I’m treating like I do by using the higher Cl levels. Running pump 24/7 and using skimmer/main drain for circulation. But, here are my questions (any other feedback most welcome on the other details, too)
- I had a pool pump repair done recently done by a pool company and the algae issue started soon after. I noticed they used their own bucket to take pool water to prime the pump. I am wondering if that could be a source of the algae? Maybe too Covid-19 sensitive, I guess!
- Every time now I’m adding the Leslie’s stuff, and testing about 40 min later, I am consistently getting results I’d expect with 6% bleach, so I have to assume the shock lost its full effectiveness. Would anyone disagree? I’ve read threads on how one can test bleach, but haven’t tried them (Taylor kit / bathtub test). Also, could there possibly be anything else wrong with the shock that could cause water contamination? It smells like chlorine, if yellow, and is giving me chlorine rise. My wife’s telling me stop using it. I only have 3 gallons of it left so will be then using leftover Walmart bleach from last season.
- I know for mustard algae, it’s recommended to thoroughly sanitize everything in and outside the pool. What’s the recommendation for a solar cover? Keep the cover on or off during the SLAM?
- Similarly, what about a heater recommendation? Should this be run at some point during/after the SLAM (and for how long) so the high Cl can ensure the heater gets sanitized? I’ve been using the heater on and off the last few weeks, so I’m guessing it needs to be sanitized.
