Suggestions on causes of cloudy water

[mknauss]

I lost 6.5 of FC today.

You might consider bumping your CYA to 50 ppm for the next several weeks while the UV is strongest. Especially if your pool is in sun most of the day.

 

[JW1]

OCLT test was .5 and CC is O this morning before sunrise. Yesterday morning the water was crystal clear. So at this point I will try today to keep the solar cover on and test throughout the day to see how the FC responds. Weather is to be in the mid to low seventy’s with a UV index high of nine at 1 pm.

 

[LoneWolfArcher]

Are you still running the automated vacuum?

What I find is that when first opening for the year, after I kill any and all algae. I run the filter 24/7 as the pool is clearing the fine powder particles of dead algae. Over time it will all settle to the bottom. If I try to vacuum with my normal vacuum roller head then it stirs it up and clouds the water again. If I use a pvc pipe pushed into the end of vacuum hose and slowly hold it over the powdery dead algae, I can vacuum it up without stirring it all up. It is tedious and takes time but then the water stays clear. I am wondering if the automated vacuum is stirring up that fine powder dead algae and reclouding the water with each usage.

 

[duraleigh]

What I find is that when first opening for the year, after I kill any and all algae. I run the filter 24/7 as the pool is clearing the fine powder particles of dead algae. Over time it will all settle to the bottom. If I try to vacuum with my normal vacuum roller head then it stirs it up and clouds the water again. If I use a pvc pipe pushed into the end of vacuum hose and slowly hold it over the powdery dead algae, I can vacuum it up without stirring it all up. It is tedious and takes time but then the water stays clear. I am wondering if the automated vacuum is stirring up that fine powder dead algae and reclouding the water with each usage.

That's a workable plan but there's a downside to that. The algae lying on the floor is often not all the way killed and it is possible a lot of it can "hide" from the chlorine. I would rather see folks vigorously vacuum, catching what they can, but the remaining "junk" is then swirled up into the chlorinated water and it can be killed completely and then eventually caught by the filter.

I have read many threads wherein people do not want to disturb the stuff on the bottom because their water will no longer be clear.......I believe it is best to disturb the water as much as you can and let your filter do what it's intended for.

 

[JW1]

Lost 1.0 ppm of LC with pool covered all day.

 

[LoneWolfArcher]

That's a workable plan but there's a downside to that. The algae lying on the floor is often not all the way killed and it is possible a lot of it can "hide" from the chlorine. I would rather see folks vigorously vacuum, catching what they can, but the remaining "junk" is then swirled up into the chlorinated water and it can be killed completely and then eventually caught by the filter.

I have read many threads wherein people do not want to disturb the stuff on the bottom because their water will no longer be clear.......I believe it is best to disturb the water as much as you can and let your filter do what it's intended for.

Even after passing the OCLT?

 

[duraleigh]

Even after passing the OCLT?

I don't think I understand the question

I don't see any connection between OCLT and how to best get debris off your pool floor. please clarify

 

[LoneWolfArcher]

I don't think I understand the question

I don't see any connection between OCLT and how to best get debris off your pool floor. please clarify

You said the dead algae debris at the bottom could be comprised of living algae too. My advice on vacuuming in a manner as to not stir up that debris was for after the passing of the OCLT, signifying there was no organic material still living in the pool.

 

[duraleigh]

signifying there was no organic material still living in the pool.

I think I understand better now. I wish the OCLT was rock solid scientific factual evidence that there was nothing living in the pool but it isn't quite. It's a pretty good indicator but not 100% absolute.

Think of the debris on a pool floor as a pretty good hiding place for nurturing and stimulating new algae growth. I believe it is better to remove that hiding place as completely as possible by brushing it up into the chlorinated water allowing the FC to thoroughly kill it and the filter to capture and remove all of it. Your vacuuming technique is workable but I don't think it provides the same level of thoroughness as lifting all of it up into the chlorinated water

 

[33Mike]

Thanks for the great discussion on here. I think I'm starting to understand my situation a bit more. To reply to some other comments above: I'm still running the S200 and I don't have evidence that there is debris on the bottom getting stirred up. I did switch to the ultra fine cartridge filter in the S200 just in case.

I believe my accelerated FC loss in the sunlight is due to having not enough CYA. Today, for example, I noticed a drop from 8.0 ppm to 4.6 ppm in about 2 hours with no evidence of CC but it was with pool in full sun and the the sun directly overhead (between 1:15 and 3:15 PM). After about 6P the pool is in the shade and I see loss more like 0.5 ppm per hour.

Today I also received my pint of CYA reagent and repeated the CYA test. I did this twice. I followed the advice elsewhere on this forum to add the turbid solution to the 50 line, glance with direct sun on the vial for the dot, then fill to 40, repeat, etc. When I do this and also compare with the images on the Taylor web page, I conclude my CYA level is less than 30 ppm. I attach my test image at 30 ppm and the references from Taylor. There is no way I have 50 ppm -- maybe there was some loss since my last test or operator error, like testing in the shade.

So, maybe the cloudy incidents that I've had in the past are just onset of algae problems due to FC loss from UV. When the pool is covered FC loss is less than 1 ppm per day, similar to what JW1 reports. Last year, the pool was covered during peak sun at least 5 days a week as we were at work. Now with COVID-19 it gets opened daily and this, coupled with low CYA may be the difference in chlorine consumption between this year and last year.

I will attempt to increase CYA by 20 ppm and see if that gets me in the 40 ppm - 50 ppm range and then see how consumption changes.

Thanks again for everyone's help.

 

[mknauss]

I followed the advice elsewhere on this forum to add the turbid solution to the 50 line, glance with direct sun on the vial for the dot, then fill to 40, repeat, etc.

Stand outdoors with your back to the sun and hold the view tube at about waist level. If sunlight is not available, find the brightest artificial light you can.

There should not be 'direct' sun on the vial. There should be 'indirect' sun on the vial.

 

[33Mike]

There should not be 'direct' sun on the vial. There should be 'indirect' sun on the vial.

Good to know. I don’t think it changes my conclusion. I actually did the test first exactly as you describe with the vial in the shade of my body. That photo with the vial filled to the 30 ppm level is attached. When I keep my back to the sun, but move the vial out of the shade of my body the dot is, of course, more visible.

 

[mknauss]

It is up to your interpretation when you do the test. Pictures I cannot give guidance on --

 

[33Mike]

An update: I continued on with CYA at 50 ppm. Chlorine use was acceptable but water, while OK, was still not crystal clear. I knew I had it clearer last year.

Unfortunately a controlled experiment is hard - what happened next was unexpected.

I opted to clean and apply UV protectant (an annual treatment) to my safety cover. The protectant is made by the cover manufacturer. It looks like armor all and smells like coconuts. Instructions say apply and leave to dry. Well, the cover looked great, but repeated opening and closing apparently transferred protectant to the underside and into the water. I could notice a slight oil slick and chlorine consumption went up dramatically. Water got a bit cloudier than “acceptable.” After several days I tried rinsing and scrubbing the cover with water. That seemed to get rid of some of the greasiness, but increased chlorine demand remained and I lost the ability to try to discern a correlation between water quality and chlorine demand.

Now, the interesting part. We had two days of pretty high bather load. I kept the chlorine level up throughout. On the third day, I went out to find very little jet pressure. My filter runs about 17 psi clean, and when I went to the platform it was reading just over 30 psi. Coincidentally (or not) after this event the pool is sparkling clear. I attach my trophy photos. In the second you can see the sharp shadows of the jet on the bottom of the pool at the 6ft deep end. This is as clear as I’ve ever seen it, and at the same time, I‘m still using significant chlorine a few ppm overnight, maybe due to remnant UV protectant.

My guess is the filter plugged up with all the people and constant churn of water, then it started filtering really well and got rid of what ever suspended junk I had lingering around. It must have happened pretty rapidly, because I can run for 1-2 weeks without seeing significant pressure rise. (This is somewhat consistent with the observation of LoneWolfArcher that is posted earlier in the thread: low chlorine demand but very fine particulates suspended in the water.) This is a sand filter and I have been adding DE after backwash to get 1 psi rise. Is anyone more aggressive with the use of DE, maybe as a one-time cleanup effort? Hopefully it will stay clear.

Thanks again!

 

[duraleigh]

Wow! That is clear water. Your ten posts are not indicative of your TFP knowledge. You grasp this stuff incredibly well.

Is anyone more aggressive with the use of DE

Probably not (or shouldn't be, anyway) The 1 psi has always been a standard that seems to work pretty well. Doing a BUNCH more is problematic for sure so I would suggest not more than that one psi standard.

I think your theory as to why it cleared so quickly is right on the money, too. Very nice work!

 

[LoneWolfArcher]

Wow is that sparkly!

One thing I've noticed. This year I've cut down on the number of hours I run my pump last year I ran it 8-10 hours. This year I am running it 4-6 hours.

My water is not nearly as crystal clear at is was last year. It is clear, but not sparkling like yours is right now. I know there are a lot of opinions about running the pump, and theories on water turnover, etc. However, I've also seen information that running your pump, 24/7 if you can afford it would be ideal.

Obviously, I am not advocating 24/7 pump usage. But I am of the camp that 5 hours is better than 4...and so on. I am considering bumping my pump running time back up and seeing if my water clears even more.

How long have you been running your pump?

 

[33Mike]

Recently, I've been running the pump 24/7, and all last year I ran 24/7. I've had the pool for just over a year and last year I was focused on a lot of other things related to it (landscaping, new patio, new lawn to replace the mud pit created by construction, etc.) and decided to defer emphasis on power consumption, but addressing power was very high on my winter "to-do" list. The pool was built with a single-speed pump and running 24/7 it consumes about as much power as our entire house in the summer. (For fun our daily power use for March is attached -- can you guess what day I opened the pool?)

In order to allow reduced running, I built a Wi-Fi control box. Having a gas heater, I can't quite use simple off-the-shelf timers because the right thing to do is cut the heat about 5 minutes before cutting power to the pump to allow the heat exchanger to cool. Also typical Wi-Fi switches are not rated for the current draw of a pool pump, so programming a pair of them is not an option. I built a little box that uses a basic 3-button Wi-Fi switch to control relays that in turn manage the pump, heater, and pool/spa mode toggle on the heater with appropriate time delays so if the heat is on and the pump is switched off, it will run for an extra 5 minutes. (The box has bypass switch that reverts control to standard outdoor toggle switch on the platform, which is helpful for backwashing and other maintenance where you want easy manual control of the pump.) It has worked marvelously, but I've been fighting less than sparkling water. And that is kind of what started this whole thread.

Now that I've had multiple consecutive days with crystal clear water, I think I'll restart this program of trying to shut down the pump. I'll start with turning it off just 5 hours overnight, and then maybe increase if the water stays clear. Trying to shut down the pump was also a motivator to move to liquid chlorine because I can disperse a sizable chlorine dose in tens of minutes rather than running the pump for hours with tablets. I'd be happy if I could get to running 12 hours a day. Based on what I've read that should be no problem. I plan to do it in cycles of say 4 hours on and 4 hours off. If I can push to 3 hours on 5 hours off (9 hours per day) it would be a wonderful improvement.

 

[LoneWolfArcher]

Very interesting. Would love to know more about your WiFi control box. I'm pretty handy with electronics so I think I could build one too.

I'm on a single speed pump too. It is on its last leg, so next year I'll be replacing with a variable speed pump.

I was out testing and adding LC tonight, and cleaning the skimmer sock and skimming the pool. My water is pretty clear. I think the "it isn't as clear as last year" thing is all in my head.

 

[33Mike]

I should amend my note above: *inexpensive* off the shelf switches won't easily work. I understand there are full control systems that are built just for pools. However, I don't have water features, or a built in spa or anything.

I was looking for two main features: (1) ability to manage automatic pump shutoff with a heater in the system and (2) the ability to toggle from heat to spa mode on the heater so that while away for the day at work, I could preheat the pool if the weather was looking favorable for an evening swim. This let's us use the pool early and late in the season without having to keep it at 90 F all the time. I was able to build this for around $100 or so with parts from Amazon. Because the primary control interface is a standard WiFi switch you can control it with Alexa (or your favorite home automation system), your phone, or toggling the switch by hand. I drew up some circuit schematics and have part numbers. I'll post a writeup in a new thread in the equipment forum to avoid "thread creep" and link back to this. (Warning: not UL listed, use at your own risk, only intended to be built and installed by a professional electrician, not responsible for injury or equipment damage .... all usual disclaimers apply!)

 

[33Mike]

I think the "it isn't as clear as last year" thing is all in my head.

I've found a good way to judge is to look at the light at night. You can even take photos for the record. To do so, stand just behind the wall that the light is on so that the light itself is not visible, but you could see any halo or glow that is a few inches directly in front of the light. (I suppose you must have a certain pool geometry for this.) Then judge the size of that glow. That is the scattered light from particles right in front of the light. If the water is obviously cloudy this will look like a locomotive going through the fog, but I find it is sensitive to judging "how clear is clear" and it is one you can photograph rather than having to rely on memory.

I attach two photos. My fault for not using the same pool light, background lighting, aspect ratio, etc. These from before (green light) where my water was OK but not sparkling and after (blue light) taken around the same time as the photos earlier in this thread. In the second you can even see it looks like the camera auto-focus picked up on the texture on the floor of the pool. It is important that the light not be directly visible because I think it will create a halo itself when it goes into your camera. And would probably be a good idea to use the same color and similar time of night to get same exposure, etc. It may help with trying to determine if "it isn't as clear as last year" is really in your head.