Filter + Pump size and cloudy water

[Sanchz]

Hi, this is my very first post.

Note: I'm in the middle of summer where I live

The problem: Cloudy pool water (drain cover is barely visible).
Test results:
pH: 7.4
Total Chlorine: 15

The thing is, I can't get a proper test kit since they don't sell those in my country. I'm not even sure that the TC reading is right. I've got some strips that test TA but they're a year old and read 70-80, and CYA at around 20 but I'm quite sure it's way higher.

Description: For the past 2 seasons, the water seems to get cloudy after a while, even though pH is corrected every three days (it tends to rise quite a bit) and I add chlorine every 2 days (sometimes Dichlor, sometimes Liquid Chlorine). A litlle bit of algae shows on the bottom at the sides and when it does I add like 4 times the dose of chlorine and brush.
The main issue is that every time I get cloudy water I run the sand filter for about 16 hours and the water doesn't get even slightly more clear. And the filter doesn't seem to clog up after a while, the pressure remains constant. What is more, I don't think the filter did any acceptable filtering since the pool was built 5 years ago. The only way of clearing up the pool is by using flocculants which take 3 days to work.
I've opened the filter to inspect the sand and though it's roughness and level seemed fine, it was not flat inside the filter: it was uneven and cone-shaped around the main pipe.
All this led to the suspicion of channeling since (see my signature) a bit of investigation made me notice that the pump may be oversized for the filter's capacity.
Getting a new filter (bigger one) is quite expensive, and pool professionals are such morons over here (they just tell you to check the pH, they don't ever question the filter's efficiency or actual state).

Is there any way to be sure that the filter is the culprit? Is it? I'm really fed up with this and annoyed too, since I read in every website that sand filters should be able to get the water crystal clear.

Thanks for reading.

 

[JohnT]

Welcome to TFP!

I'd be willing to bet your problem is that the pool isn't being chlorinated often enough. Daily chlorination is much better. Cloudy water is the first sign of algae, and it will take a few days to clear it even if you do raise the chlorine level.

I think you already know that you need better testing supplies. Post your country and maybe someone else knows how you can get what you need.

 

[Sanchz]

I'm in Argentina and it's quite impossible to find/import any test kit but the basic pH + Total Chlorine test kit. I only got some strips from a trip and I think they're not accurate at all.

I forgot to mention that I have 2 pucks of trichlor in a floater at all times.

Two days ago, when I first saw the signs of algae and turbidity I added about 4 cups of dichlor plus 2.5 gallons of liquid chlorine and some pH reducer to counteract the latter's high pH.

 

[thepoolman]

Sometimes using a little DE powder or other filter aid in the sand filter will help make the filter more effective. It fills in the holes and allows it to filter smaller particles. If you do something like that and see a difference, filtration could be part of your issue.

 

[Sanchz]

I did add DE a couple of times; only once did it leave the water crystal clear. All other times it caused pressure to increase too much too quickly so that the flowrate reduced too much to be effective.

 

[thepoolman]

Yeah. It's definitely a temporary solution, but it can help you determine if filtration is the issue or not.

I am surprised you are not able to get a Taylor test kit from a larger online distributor. Are there no pool stores there?

 

[Sanchz]

There are pool stores, but all sell the same stuff. Online distributors have issues shipping the kits because they are considered "hazardous materials" and our customs are also REALLY restrictive on what kind of stuff you can get in.

 

[Buford]

There are pool stores, but all sell the same stuff. Online distributors have issues shipping the kits because they are considered "hazardous materials" and our customs are also REALLY restrictive on what kind of stuff you can get in.

Taylor sells to Horner Express who does most of the international sales, other than Canada. You might check with them and find out who carries the line in your country at http://www.hxworldwide.com/ [email protected] or you may try their Spain location [email protected] I do not know if they will sell to you, but they might.

I don't know about where you live, but here, importing goods into the US can be a daunting task, with the risk of never receiving your order. That is why I would try to find the product domestically. Good luck.

 

[Sanchz]

I'll give it a try, but I've never ever really saw any other test kits. Plus, I don't even know if they'd be in good condition at all.
Every year when I try to look for a solution I stumble across this problem and don't get much help online.

Anything I can do/try? Could there STILL be any problem with the filter (I believe it's undersized)? As I already said, it never ever really cleared the pool any bit.
And I know there's a physical (suspended particulate) side to the problem, since clarifiers do work and send it all clumped to the bottom.

 

[Buford]

I am at a loss. All my cloudy water has been a problem with the chemistry. Without any accurate test results, it is impossible to know what direction to go.

It might be possible you used too much DE when you tried. You might try reviewing the instructions ( pool-school/add_de_to_a_sand_filter ) and make sure you only put in enough to raise the PSI by 1 .

Another thought, could you have started cleaning out the small particulate for a short time after you used the DE and the clogging was caused by the particulate? If that is the case, you would need to reintroduce DE into the filter after each backwash.

If you really believe it is filtration problem, you might try searching google (bottom left of this page) on articles about cleaning sand in a filter. One of them is here my-sand-is-channeled-how-to-fix-it-t7626.html I have no idea if cleaning the filter sand will help.

Maybe someone else will come up with a solution. Good luck.

 

[Bama Rambler]

One clue you gave us that it's a chemistry problem is when you said

I did add DE a couple of times; ... All other times it caused pressure to increase too much too quickly so that the flowrate reduced too much to be effective.

This tells me that it was filtering out stuff that was in the water and was doing exactly what it was supposed to do. You need to get all the stuff killed so the filter can filter it out. Then it'll get clear and as long as you keep the chems right it'll stay that way.

 

[Sanchz]

I think it might be a chemical problem too. The thing is, I do regularly add chlorine and the test kit always shows at least 3 ppm of TC;
but since I don't really know the CYA levels, it apparently is not enough to kill everything in the pool.
I really feel like I'm working in the dark because of the lack of test results; but there are LOTS of people here that get by with crystal clear pools without them too.
Another thing I'd like to repeat is that since the last sand replacement, the filter on its own doesn't appear to get clogged even after 3 weeks of use.

Also, what level of clarity could a sand filter normally achieve?


Note: We called the pool guy today, he told us not to worry about the high pH caused by liquid chlorine, to add more chlorine, and to work as if we didn't have a filter (just use clarifiers).

 

[zea3]

A sand filter will give good clarity, but it takes longer to filter out dead algae than a DE or cartridge filter. Let's see if we can "guestimate" what your CYA level could be. How long have you owned the pool and what do you normally use as a source of chlorine? Have you ever partially or completely drained and refilled the pool? Do you have a heavy rainy season? Do you regularly use chlorine floaters?

If you are unable to locate a supplier for the test kit you need, the solution may be to drain and refill the pool, then keep a record of how much of each chemical is added and when. Also log weather events like significant rainfall, or extended drought conditions. That would at least give you an estimate of the chemical levels when you can't locate the right testing materials.

 

[Sanchz]

The pool was drained two years ago; but it gets about 2-3 inches of fresh water each week because we vacuum to waste. No rainy season, regular use of floaters, have been using liquid chlorine since December but have just turned to dichlor powder. I believe that with the amount of water I replace each week it should not be a problem. Also, some test strips that somehow measure CYA actually show low CYA levels (about 40 ppm).

As of now, some flocculant cleared the pool yesterday, today it looks great; and with more constant addittions of chlorine and DE in the sand filter I hope I'm good to go.

One question regarding DE in the sand filter: I see the pressure building up after about 2 hours of filtering, but when I stop the pump and turn it on at a later time, the pressure gets back to "clean" levels and then again slowly climbs up. I'm guessing this is because the DE is re-setting in the sand each time, right?

 

[audone]

I have been dealing with a pool for several years that has similar problems as yours I finally got things under control about 3 years ago. I operate a 50,000 gallon pool at an HOA that averages 60 swimmers a day. My turn over rate is only about 2.75 times a day and I have an undersized filter.

First thing I would re-check your sand filter it sounds like it has not built up pressure like it used to after you last changed the sand are all the laterals ok? Are your pressure gauges working? You might consider changing your sand to one of the new products similar to zeo Bright it can filter out smaller particles. I also tried DE only used about one cup at a time to keep pressure from building up to quickly. I found it helpful but no longer need it after I made the changes below.

I switched to chlorine free shock this way my total chlorine would not get so high you stated yours was 15ppm. Shock and some types of chlorine can have a high pH. High pH can cloud your water and make your chlorine less affective.

I stopped using clarifiers they can be part of the problem especially if used every day. Instead I started adding salt pellets the type used for water softeners; I would start with about 10 pounds then about 5 cups a week. I just put them in a skimmer and let them dissolve. It gave our water a sparkle it had never had. Salt also rejuvenates the filter medium if you switch from sand. (I read about this tip on line)

We brush all the walls of the pool 3 times a week and vacuum everyday, I stopped using a kreepy Krawly it didn't get to all the areas of the pool and didn’t allow the pool to filter as well.

Our pool stays beautiful about 95% of the time, before it was only clear about 40% of the time. I don’t know if you will have access to chlorine free shock or different mediums other than sand for your filter. But since you can’t accurately check your chemical levels, check the pH of the type of chlorine you are using to make sure it’s not part of the problem. I also buy chemicals with as few additives as possible my chlorine tabs don’t have softeners or clarifiers added. Try different brands of chemicals some brands cloud up our water almost instantly. Good luck

 

[Sanchz]

Ok so today the water was crystal clear, with about 1.2 pounds of dichlor added the night before, and it received 5 swimmers for about 2 hours, and now it's cloudy again. Not THAT cloudy but noticeably cloudy. pH is about 7.3 and I have just added 0.7 pounds of dichlor to combat the contaminants. I really don´t think this number of swimmers with positively high chlorine levels and correct pH can cause such a mess. Been running the filter with DE all the afternoon and will hopelessly leave it running overnight.

audone, I´m keeping a weary eye on pH levels, so I´ve ruled that out. I can´t get any zeolite over here, and I don´t think the laterals are damaged since no sand whatsoever has been seen on the pool. I might change it sooner than later. The only strange thing is that the sand´s surface is quite uneven inside the tank after some hours of use. Do you think that adding salt will improve things?

Also, the paint is 1 and a half years old and it´s kind of dull and gives off some kind of chalky dust trail when rubbed against strongly, but I don´t think it is to blame for the constant cloudiness.

 

[audone]

If you added dichlor the night before you had swimmers could some of that have settled on the bottom then the swimmers stirred it up causing the pool to cloud up a little. I notice that happens at our pool after I shock it.

Probably just chemical residue left after water has evaporated. Another thought how is your calcium hardness level your pool might be leaching calcium from walls.

I know your frustration I was there a few years ago. I did exactly what you are doing searching the internet for solutions. The salt worked for my pool along with not using clarifiers and brushing my pool several times a week and vacuuming daily. (Please realize this is a commercial pool with high use so I have to do things more often).

Several pool sites online said I should not have to use clarifiers, this went against everything I had learned. I had religiously been adding clarifiers at least a couple times a weekly. The first season I stopped adding them was the clearest the pool had ever been. I read about adding salt at another site I didn’t see how it could hurt that’s when the pool started getting that pristine clear sparkle. The salt also gives the water a nice soft feel. A friend of mine whose mom has a pool tried adding salt and had the same results. Will salt help your situation can’t say for sure but it’s cheap and worth a try.

It’s just been a process of elimination if I use the soda ash from one company my pool will cloud up another brand works fine same with the chlorine tabs. That’s when I started buying chemicals that have as few additives as possible.

 

[Sanchz]

Thanks for your response audone!
I'm sure that dichlor does not settle at the bottom nor does it cloud the pool. I have no idea what my CH level is, but do you think it's to blame? I don't regularly add clarifiers, just flocculants (then vacuum to waste) when I'm out of options (quite often, that is). The pH reducer doen't seem to make it any worse, I've used plenty of brands and none seem to be direct producers of cloudiness.

I don't brush the walls unless they start to get green, since that's an easy way to get the water dirty again. Should I brush even without visible dirt in them?

I can get chlorine-free shock, but I've used it under these conditions with no luck. Also, I use trichlor tabs in a floater at all times, do they have any kind of unwanted additives?

Is it okay if I use regular, cooking salt?

As of today, (been running the filter non-stop since yesterday, with added DE) the pool is not perfect but better than yesterday night.

I just don't know why it got THAT dirty (cloudy) with a relatively normal amount of swimmers. I even considered leaving it cloudy (but clean) and just live with it.

 

[George N]

http://www.troublefreepool.com/pool-school/basic_pool_care_schedule states brush or vac weekly.

Do NOT use table salt!

 

[Sanchz]

Noted, no table salt. I've just brushed it.