Return of the Mustard Algae!

The pool chemistry is what keeps the pool nice, not a certain amount of runtime or water turnover.
100% correct.


But when you produce FC wth the SWG is a ***huge*** factor in staying clear. If you run 4 hours in the middle of the day, you will have a little swing in FC, but not alot.

If you only produce at night, your pool swings 4 ppm or even 5ppm daily, (because FL) just like a liquid chlorine pool.

Targeting a 5 was a fools errand, which is why the charts were adjusted with a range, with said 5 being the lowest that anyone would want to touch. I have been a SWG user since 2012. I am a SWG ninja and could fiddle with it to keep me .5 or 1 FC above min at all times as the sun depleted my FC. I could slice that line razor thin and never get algae. And what do I do with that skill ? I set the SWG to run the high side of target or over, then step in if it hits a teen.

I don't want to watch it like a hawk on the low side. If you don't watch it like a hawk, you get bit as you saw here. So those of us with better things to do run it hot, which means we have more wiggle room to catch it low. We all bought SWGs for less work, not more work.
 
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100% correct.


But when you produce FC wth the SWG is a ***huge*** factor in staying clear. If you run 4 hours in the middle of the day, you will have a little swing in FC, but not alot.

If you only produce at night, your pool swings 4 ppm or even 5ppm daily, (because FL) just like a liquid chlorine pool.

Targeting a 5 was a fools errand, which is why the charts were adjusted with a range, with said 5 being the lowest that anyone would want to touch. I have been a SWG user since 2012. I am a SWG ninja and could fiddle with it to keep me .5 or 1 FC above min at all times as the sun depleted my FC. I could slice that line razor thin and never get algae. And what do I do with that skill ? I set the SWG to run the high side of target or over, then step in if it hits a teen.

I don't want to watch it like a hawk on the low side. If you don't watch it like a hawk, you get bit as you saw here. So those of us with better things to do run it hot, which means we have more wiggle room to catch it low. We all bought SWGs for less work, not more work.
I agree with you. That’s why I’m going to set my new target at 8-10. I do set my run times for mid day so no issue there. The only reason I was running 5-6 as my target is because that was slightly over what the target of chart called for as a target. Now that I have the new chart I’ll adjust accordingly.
 
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That would be one alternative, but not a very energy efficient one. I do have a variable speed pump and have it running at a lower setting most of the time. From my reading on here the recommended chlorine levels are lower for a SWG vs a pool where chlorine is added manually. Presumably because daily chlorine addition minimizes swings in chlorine levels. Even in my pool’s current condition, it only dropped from 5.5-3.5 in a week and a half period. I think the better solution is to maintain a higher chlorine level so that when there are seasonal swings it has a lot more room to drop than it currently has and it doesn’t needlessly increase my energy bills.
I’d almost put you in the manual chlorination box. My pool pump running 24x7 barely changes my power bill once we open the pool. The AC getting turned on does make a noticable difference though.
 
Hello, fellow Floridian. I’m here to encourage you to join #TeamRunHot. Since you are safe to swim anywhere between the minimum for your CYA and SLAM, you will save yourself a lot of pain if you dial your maintenance FC up. Target range is fine, but what happens when you neglect to test for a few days and a storm drops a bunch of leaves and yuck into your pool, or you have a bunch of people in the pool and they are all slathered in sunscreen? Or the power goes out for a few hours and you aren’t generating as much FC as you think you are? This is an even bigger concern if you go a long time between testing.

I strive for the top of target range, or even a point or two higher. And if the scenarios above happen, I’ll chuck a little extra chlorine in so I don’t have to rely on the SWCG to make up for a big deficit.

I just tested so I’m running at 7 FC and 50 CYA (I add CYA in steps with days in between so I don’t overshoot). I just added enough CYA to get me up to 70 and I’ll be aiming for 10-12 FC, or even a bit higher since I’m going to be out of town for a bit and want to guard against unforeseen circumstances.

Also, as said by others, try to test more frequently. And definitely do regularly check your filter.
If your a little above goal of FC of 10, how much will FC of 12 alter your pH accuracy?
 
If your a little above goal of FC of 10, how much will FC of 12 alter your pH accuracy?
I don’t know, but I don’t have to test my ph more than once a week, thankfully. When I get back from my trip I’ll let it fall below 10 to check it, then back to regularly scheduled programming!
 
I’d almost put you in the manual chlorination box. My pool pump running 24x7 barely changes my power bill once we open the pool. The AC getting turned on does make a noticable difference though.
I suppose everyone’s pool equipment is different. When I had my pool in East TN (I see you live there), the early spring months where I was opening my pool caused a spike in the energy bill and it was before the temps rose to the summer heat. That was a very old school pool with a single speed pump and I ran it 24/7. Due to trees, running it part time always seemed to result in a messier pool. With my current pool I have a variable speed pump set at 2600rpm. I set it up this way after my first electric bill that I received after the pool build. The builder left the pump at full speed running 24/7. After the change the change in my electric bill was cut in half.
 
Chances are you can run at less than 2600 RPM.

With a clean filter - determine the minimum RPM that allows your SWG flow switch to close (allows SWG to produce chlorine). As long as this RPM is at least 1000 RPM, add 200 RPM to that number (to account for filter getting dirty) and use that RPM as your baseline. Now determine if that baseline RPM is sufficient to skim the pool surface - if so, run at that RPM except when needing a higher RPM to possibly run a pool cleaner.

For my setup, I run 24/7 on pump amd SWG. At 1200 RPM for 20 hours and 2900 RPM for 4 hours (two 2 hour segments for my IFCS). Running 24/7 costs me less than $20/month - for pump and SWG combined. Others that run 24/7 have reported similar operating costs. What is your electric rate per kilowatt hour?

When running 24/7 with both pump and SWG, you are adding a little FC throughout the entire 24 hour period. If maintaining target range, there is a lesser possibility of getting anywhere near minimum when running 24/7. If you are running pump and SWG less than about 8 hours per day, consider using the non-SWG FC/CYA Levels. This will provide a higher minimum FC.

Fill out your signature with pool, pool equipment (including manufacturers and model numbers) and test kit info.
This assists us in providing you help without needing to ask you each time for this important information.
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I suppose everyone’s pool equipment is different. When I had my pool in East TN (I see you live there), the early spring months where I was opening my pool caused a spike in the energy bill and it was before the temps rose to the summer heat. That was a very old school pool with a single speed pump and I ran it 24/7. Due to trees, running it part time always seemed to result in a messier pool. With my current pool I have a variable speed pump set at 2600rpm. I set it up this way after my first electric bill that I received after the pool build. The builder left the pump at full speed running 24/7. After the change the change in my electric bill was cut in half.
Yep, my pool is surrounded by trees, bushes, lots of critters. My skimmers can fill up quite fast even running much slower RPM. You’re free to do what you like, but know the power savings is not linear with RPM so running the pump 50% slower saves more than 50% power. Just trying to save you a few bucks.
 
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Chances are you can run at less than 2600 RPM.

With a clean filter - determine the minimum RPM that allows your SWG flow switch to close (allows SWG to produce chlorine). As long as this RPM is at least 1000 RPM, add 200 RPM to that number (to account for filter getting dirty) and use that RPM as your baseline. Now determine if that baseline RPM is sufficient to skim the pool surface - if so, run at that RPM except when needing a higher RPM to possibly run a pool cleaner.

For my setup, I run 24/7 on pump amd SWG. At 1200 RPM for 20 hours and 2900 RPM for 4 hours (two 2 hour segments for my IFCS). Running 24/7 costs me less than $20/month - for pump and SWG combined. Others that run 24/7 have reported similar operating costs. What is your electric rate per kilowatt hour?

When running 24/7 with both pump and SWG, you are adding a little FC throughout the entire 24 hour period. If maintaining target range, there is a lesser possibility of getting anywhere near minimum when running 24/7. If you are running pump and SWG less than about 8 hours per day, consider using the non-SWG FC/CYA Levels. This will provide a higher minimum FC.

Fill out your signature with pool, pool equipment (including manufacturers and model numbers) and test kit info.
This assists us in providing you help without needing to ask you each time for this important information.
Be specific. See my signature and others for inspiration.
Messed with pump speed a bit yesterday but ran short on time. I can tell you that at 1200rpm the water does not flow over the spa spillway into the pool, which, IIRC was what I ran into last time I made adjustments. Going to mess with this more and try biasing the spillway more with the handy valve to see what I can do while still allowing some flow to the return jets.
This is probably obvious but if I’m currently running at 90% to maintain 5-6, runtime will be increasing regardless of what I do with pump speed so I'll most likely be over 8hrs runtime. Which should also help maintain chlorine levels.
For electric, my normal rate is 16.73c/kwh and anything over 1,000,000kwh is 19c/kwh (I’m usually in this range during summer months). That includes fuel charges and energy charges but does not include other taxes and fees. I do understand that the pump power usage is not linear also.
I had filled out my profile a while back but will update again soon since it’s no longer visible. For now, I’m using the TF-100 PRO with salt for testing and have Jandy equipment. I’ll fill in the rest of the details when I have more time.
As for the algae, somehow I ended up bringing it up to a chlorine level of 35 (CYA 65) on Saturday night, instead of the normal SLAM level of 24. Tested Sun around 10:30AM and it was down to 32 so added another gallon of bleach to bring it back up to 31.5 by Sunday night. This morning (Monday) it was down to 26. Since it is back to normal SLAM level I will most likely restart the process this evening once I purchase more bleach. Then once pass the overnight chlorine test I’ll get back to the MA level. As for appearance the pool looks much better already and I have brushed and vacuumed three times since then along with getting every little nook and cranny with a brush.
 
I may have missed it, but I didn't see what type of filter you have.
If it's a cartridge filter then this may apply.
I dealt with mustard algae for 3 years, doing the same procedure, and it always seemed to come back.

I think I found the culprit. I have two sets of four for my Hayward cartridge filter. The spare set would be in the garage while I was treating the mustard algae, and I think I reintroduced it every time when I swapped filters.
 
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Do you have automation?
Do you have a heater bypass?

With automation you can set up spillway mode to allow your spa water to refresh a few times daily for 15-30 minutes. No need to have the spa oferflow into the pool constantly any time the pump runs. Spillway mode will also keep the spa sufficiently chlorinated.

A heater bypass will bypass the hewter and reduce the restridtion of the heater on water flow. This will allow running the pump at a lower RPM as well.

Fill out your signature with pool, pool equipment (including manufacturers and model numbers) and test kit info.
Be detailed. This will assist us in providing you help without needing to ask you for this important info each time.
 
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Do you have automation?
Do you have a heater bypass?

With automation you can set up spillway mode to allow your spa water to refresh a few times daily for 15-30 minutes. No need to have the spa oferflow into the pool constantly any time the pump runs. Spillway mode will also keep the spa sufficiently chlorinated.

A heater bypass will bypass the hewter and reduce the restridtion of the heater on water flow. This will allow running the pump at a lower RPM as well.

Fill out your signature with pool, pool equipment (including manufacturers and model numbers) and test kit info.
Be detailed. This will assist us in providing you help without needing to ask you for this important info each time.
I apologize for disappearing for several weeks. I just had about the most stressful month I’ve had in the last decade. Anyway, I have filled out my pool information although the variable speed pump label is half faded away so I’m unsure of the exact part number. As for the pool, it’s looking great again and I’m currently running it at 2400rpm, which allows overflow from the spa but does not have a nice sheer pattern. Running 12hrs a day and it seems to be maintaining a chlorine level of 8-10 at 90% with CYA at 60 (was keeping low due to SLAM but just boosted to 75. I’d like chlorine production to be a little higher and I’m very interested in the spillover mode so I can run at a lower speed but can’t quite figure that out. I’m not sure if I have a heater bypass but there are two pipes coming off my heater.
Also, for the cartridge filter, that’s a good suggestion. It’s getting close to time to replace it anyway as I’ve had the same one for almost three years.
 
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