Intex AG pool with cloudy water after algae

[PoolFrog]

Hello, I'm new to this forum, and I could use some help. I have an Intex metal frame pool that holds about 5,000 gallons. I use a floating chlorinator with multiple (usually 2) 3" tablets. I use Aqua Chem brand because I've always had good luck with it. The pool has a vinyl cover on it most of the week when it's not being used. When the pump is running 9:00 AM - 10:00 PM each day, a large puddle builds on top of the cover, and I had an algae bloom in that large puddle a couple of weeks ago which mixed into the rest of the pool water when the cover was removed. After many trips to the pool store to get water samples tested, using many different products and giving it some time, the water eventually cleared up over a week later. Earlier this week, I had another algae bloom despite the chlorine level being at 4-5 coming out of the last one. When I took the cover off Wed. evening, this green algae mixed in with the otherwise clean water in the pool, turning the whole pool a translucent greenish color. I cleaned the filter yesterday morning, took a sample of water to the pool store to be tested and told them what had happened. After testing my sample they said that my chemical levels were ok and suggested that I use 8 oz. of their algaecide product, which is 60% poly[oxyethylene(dimethyliminio)ethylene (dimethyliminio)ethylene dichloride] and 40% other ingredients, and let the pump run for 6-8 hrs. I did this yesterday morning, and the green tint went away, but I was left with milky cloudy water. I called the store to tell them what I was seeing at that point and asked if I should shock the water, and they said it was most likely the dead algae. They suggested using Pool First Aid to make the dead algae collect on the bottom so that I could vacuum it up. I put the Pool First Aid in yesterday late afternoon, let the pump run until the timer shut off at 10:00, cleaned the filter again this morning and then vacuumed the pool. All this seemed to do was cloud up the water even more.

I have a couple of different shock products here at home that I could use if needed, which have different ingredients. I decided to have my water tested again today, and before I put anything else in my pool, I want to share the test results here and see if anyone here has some advice. The sample of water that was tested today was collected this afternoon after the pump had been running for about 4.5 hrs. The temp. of the pool when I collected my sample was about 85.

Free Avail. Chlorine = 1
Total Avail. Chlorine = 1
Ph = 7.2
Total Alkalinity = 80
CYA = 100
Calcium Hardness = 170
Phosphates = 100

Any suggestions would be much appreciated!

 

[Bama Rambler]

The best advice I can give you is to get your own good test kit. The TF-100 is the best out there.

The results you posted from teh pool store (which I don't believe) indicate that you need to drain at least half your water. I suspect the CYA is higher than 100 so you're probably going to wind up draining even more than that.

Once you've done that you need to SLAM your pool.

 

[linen]

Welcome to tfp, PoolFrog

Well everything in those test results and your description suggests that you likely still have algae that need to be killed.

With a pool your size and style you have a couple of good options:

• 1. Do a full drain and refill, then follow this guide: http://www.troublefreepool.com/pool-school/temporary_pool_guide
  2. Or as Bama mentioned, buy an appropriate test kit so you know what levels you current water is at. See: http://www.troublefreepool.com/pool-school/pool_test_kit_comparison For you to move forward with your current water you will need to know accurately what your cyanuric acid (cya) level is. Pool stores tend to get this reading more wrong than right.

One thing if certain, following both the pool store recommendations and tfp recommendations is a recipe for diasaster. FYI, almost all of things the pool store recommended would not be recommended by tfp.

 

[zea3]

Hi, welcome to TFP! First off, do not use any more stabilized chlorine in your pool. The recommended level of CYA is 30-50 ppm. The CYA test tops out at 100, but it is likely your CYA is much higher. The only way to lower the CYA is to partially drain and refill the pool. After the CYA is lowered to 30-50 ppm you can use liquid chlorine or 8% plain, unscented bleach to slam the pool.

As mentioned earlier, a good test kit is one of the best investments you can make in your pool. A high quality FAS/DPD test kit will allow you to test the high FC values needed for the SLAM process, plus you will have consistent, accurate information to help you determine how to manage the water chemistry.

Do you use the vacuum that attaches to a garden hose to vacuum this pool? If so it will be difficult to vacuum out all the dead algae. I would recommend you vacuum the pool by the siphon method. That will drain out a lot of the high CYA water as you vacuum. Here is a description of the siphon method.

when I had a Intex, I used a standard vacuum head and hose, and set a syphon over the side instead of using the pump at all- as long as you don't mind watering the grass, and replacing water (same as vacuum to waste!)
fill hose with water- start at one end, attach to vacuum to weight/hold underwater.
push hose underwater along the length, so it fills entirely
when you reach the other end, water should bubble out of it
Hold both ends under water
grab the middle of the hose, throw it over the side so a loop is hanging lower than the water level in the pool
work back the length of the hose away from the vacuum head
throw the end on the ground where you want the water to drain
start to vacuum!
when done, lift vacuum out of water to break suction, and drain to other end so gunk doesn't come back into pool

 

[PoolFrog]

I understand that I should get a more sophisticated test kit than the one I have now that just shows Chlorine and pH. I was really hoping to avoid draining and refilling. I did that as a last resort after the first algae bloom (drained it down to about 8" depth), and I still had cloudy water when I filled it all the way back up with fresh. Plus, we're having triple-digit temperatures here right now, and the city is picky about restricting water use during these hot months (I believe we have to pay a surcharge if our household water use is above a certain limit).

As I mentioned, I have some shock products that I bought recently to have on hand. One of them is 99% sodium dichloro-s-triazinetrione dihydrate. I'm assuming that this isn't a stabilized chlorine, since it's 99% of a single active ingredient. Could this possibly help, or do more harm?

 

[linen]

One of them is 99% sodium dichloro-s-triazinetrione dihydrate. I'm assuming that this isn't a stabilized chlorine, since it's 99% of a single active ingredient. Could this possibly help, or do more harm?

Harm, it adds cya which it seems likely you already have too much.

You need to get a reliable cya value if you are going to keep your water. Once you have that you then would do the appropriate drain/refill to get your cya level down to 30-50 ppm and then do the SLAM process. For the SLAM process to be most efficient you will need the FAS-DPD free chlorine test that is in the mentioned appropriate test kits.

 

[zea3]

Any product labeled trichlor or dichlor is stabilized chlorine. Your best bet will be to use liquid chlorine or 8% plain, unscented bleach. If you are unable to drain and refill due to water restrictions, you will need to SLAM the pool according to your current CYA level. You can use the Pool calculator to determine your SLAM level.

 

[PoolFrog]

I see. I'll definitely have to get a better test kit. I didn't realize that a pool store's test would be unreliable. Thanks for the suggestions!

 

[PoolFrog]

I meant to ask, where's the best place to get a TF-100 kit?

 

[linen]

tftestkits.net

Dave (username duraleigh and also the owner of this site) has really fast shipping.

 

[PoolFrog]

The owner of this site owns tftestkits.net, too?

 

[PoolFrog]

As long as the water is safe and not harmful for swimming, I can handle it being cloudy for a little while. With the triple-digit temperatures, I'm having to add new water periodically anyway. If I stop using stabilized chlorine tablets and start using 6% bleach, is that harmful to a vinyl Intex pool, or to the pump? I've never used chlorine in liquid form.

 

[Charlie_R]

For a bit more money, and less certainty on the freshness of the reagents, you could go through Amazon.com and get the Taylor K-2006 kit.

As I understand the situation, Dave started selling the TF-100 kits as a less expensive alternative to the Taylor kits. Same goods in the kits, but higher quantity of the reagents you will use more often. Added plus -- You get a freshness guarantee from Dave that the kit reagents are the freshest he can get. Taylor kits come in two sizes, the K-2006 with .75 oz bottles, and the K-2006C with 2 oz bottles. Check http://tftestkits.net for the size of reagent bottles he gives, and you decide which is the better value.

For me, had I known about the TF-100, I would have bought that one rather than the K-2006 I have. I am still considering getting the TF-100 for next season.

By the way, How many ads do you see on this site? I'm willing to bet that quite a chunk of the profits from the kit sales go toward keeping this forum up and running.

 

[Donldson]

With the triple-digit temperatures, I'm having to add new water periodically anyway.

Evaporated water does not lower CYA, only water and chlorine evaporate. Only removing water and replacing it will lower your CYA, assuming it needs lowered. We have seen so many incorrect pool store tests that I personally wouldn't make any recommendations based on those results.

If you are worried about bias with the TF-100, know that nobody but the owner of the site is paid to promote it. I don't make a dime but still recommend it all day. You need an FAS-DPD test that is very hard to come by from local pool stores. It is included in the TF-100 and K-2006, and the TF-100 was custom designed to be most useful for the methods we teach here.

pool-school/pool_test_kit_comparison

 

[Smykowski]

You've gotten good advice from everyone so far, but no one's touched on your original problem: algae on the cover.

Because your cover will never have water circulation over the top, you need to keep it clean. If I see any green on it (which is inevitable), I pull it off and wipe it down with bleach. Maybe once a month does it. When you pull the cover off, roll it instead of pulling it to prevent the algae from sliding into the pool. Once you get the good test kit and the water is balanced correctly, any little bit that does make it into the pool will be taken care of.

Did that make sense?

 

[PoolFrog]

I didn't mean for my question about the owner of this site selling test kits to sound like a negative one. I understand that it takes money to keep this site up and running. I had seen the tftestkits site on a Google search for the kit, and just wasn't aware that the owner of this site owned that one, too.

I'm assuming that as I add water to the pool as water evaporates from the heat, the high CYA content in the remaining water will be diluted by the new water that I'm adding. Is this correct?

Regarding cleaning the cover, thank you for the suggestion. I was wondering about the best way to clean it, and was even thinking about leaving the cover off for the remainder of the swimming season, since that was the origin of all of these problems.

 

[zea3]

As long as the water is safe and not harmful for swimming, I can handle it being cloudy for a little while. With the triple-digit temperatures, I'm having to add new water periodically anyway. If I stop using stabilized chlorine tablets and start using 6% bleach, is that harmful to a vinyl Intex pool, or to the pump? I've never used chlorine in liquid form.

Chlorine is chlorine. The only difference between dry and liquid chlorine is that dry chlorine must be stabilized either with CYA, calcium, or lithium. CYA and calcium both build up in the water and can only be removed by draining and refilling. They do not evaporate out with the water. The lithium stabilized chlorine is expensive and difficult to find. Liquid chlorine is the best sanitation alternative since it will not lead to excess CYA or calcium.

The important thing to remember about chlorine dosing is that it must be in the correct ratio to the CYA level to be effective. Using the Pool calculator with your current test results will tell you how much chlorine you need to add. The recommended FC range for your pool with 100 ppm CYA is 8-13 ppm of chlorine. You never want to let it drop below 8 ppm. When you are able to drain and refill you will see the FC recommendation will go down as the CYA level goes down.

 

[linen]

I'm assuming that as I add water to the pool as water evaporates from the heat, the high CYA content in the remaining water will be diluted by the new water that I'm adding. Is this correct?

Since cya doesn't evaporate with the water as your water evaporates the remaining water after evaporation has a higher cya level, then when you add fill water to bring you level back up to the starting point, your cya level goes right back to where it started.

 

[Donldson]

I'm assuming that as I add water to the pool as water evaporates from the heat, the high CYA content in the remaining water will be diluted by the new water that I'm adding. Is this correct?

Linen beat me to it, you can only lower CYA by removing liquid water and replacing it with fresh. Same is true for salt and calcium.

 

[PoolFrog]

As long as the water is safe and not harmful for swimming, I can handle it being cloudy for a little while. With the triple-digit temperatures, I'm having to add new water periodically anyway. If I stop using stabilized chlorine tablets and start using 6% bleach, is that harmful to a vinyl Intex pool, or to the pump? I've never used chlorine in liquid form.

Chlorine is chlorine. The only difference between dry and liquid chlorine is that dry chlorine must be stabilized either with CYA, calcium, or lithium. CYA and calcium both build up in the water and can only be removed by draining and refilling. They do not evaporate out with the water. The lithium stabilized chlorine is expensive and difficult to find. Liquid chlorine is the best sanitation alternative since it will not lead to excess CYA or calcium.

The important thing to remember about chlorine dosing is that it must be in the correct ratio to the CYA level to be effective. Using the Pool calculator with your current test results will tell you how much chlorine you need to add. The recommended FC range for your pool with 100 ppm CYA is 8-13 ppm of chlorine. You never want to let it drop below 8 ppm. When you are able to drain and refill you will see the FC recommendation will go down as the CYA level goes down.

Is it safe to swim in water with 8 ppm of chlorine?