Help, Pretty Please?!! New Pool Owner Overhwhelmed by Mustard/Black Algae...

Aug 9, 2016
15
Lufkin, Texas
Hi there!

I apologize in advance for the long nature of this post. We are at our pulling our hair out & do not know what to do! The hubby and I just bought a home with a 14,000-15,000 gallon plaster pool and attached spa with Pentair IC-40 (that I now believe is not functioning due to a green flashing “cell” light). We’ve never maintained a pool before and are freaking out with this algae & this pool not holding a chlorine reading. For reference, we are in East Texas - pine trees galore and intense, humid heat frequently between 90-105 degree during the summer months.

The sellers of the home did not maintain properly and when we took possession of the home on July 3oth, we noticed what turned out to be mustard algae and black spots which I’m guessing is black algae. Of course, not knowing what to do, we immediately took a sample to Leslie’s. As of July 30th, our readings were:

Free Available Chlorine: 0
Total Available Chlorine: 0
Salt: 4200
Calcium Hardness: 180
Cyanuric Acid: 60
Total Alkalinity: 80
pH: 8.0
Acid Demand: 2
Copper: 0
Iron: 0
Phosphates: 300
Temp: 85

He told us to put in 24 oz of Muriatic Acid, to put in ONE packet of Chlorbrite and that is it! Of course at the time, everything sounded like a foreign language to us (we didn’t know the first thing about pools) so we simply did what we were told. Of course, the pool did not get cleaner nor did the algae spots clear up. So, a week later on 8/6, we take another sample to Leslie’s and tell him about the algae not clearing up. As of 8/6, the readings were:

Free Available Chlorine: 0
Total Available Chlorine: 0
Salt: 3000
Calcium Hardness: 230
Cyanuric Acid: 60
Total Alkalinity: 80
pH: 8.0
Acid Demand: 3
Copper: 0
Iron: 0
Phosphates: 500
Temp: 90

He gives us test strips, a whole box on ChlorBrite, 1 quart of “Algae Control”, some “PhosFree” and then “Perfect Weekly” to use once we “got everything under control”. He tells us to go home, backwash, then add the algae Control. Then to add the Muriatic Acid, wait an hour and then begin putting in the Chlorbrite every two hours if we still register 0 on chlorine. We get home, we completely overwhelmed and call a local pool guy. He comes out and that is when we are informed that the algae is “mustard” algae and the black spots also algae. He puts in some powdered chlorine and tells us to put in a couple more packs as well. He says to scrub the walls and that if we wanted him to put in some algae treatment he could. I knew about this forum & I didn’t want all sorts of things going into the pool that didn’t need to be, so I said we would wait to see if the chlorine would handle it and that if we couldn’t get it under control, we would call him back. I immediately started researching this forum and I learned many thing VERY quickly: I realize that we need to SLAM (shock) the pool. I learn that the the shock level should be 24. I learn that bleach or liquid chlorine should be used as it is faster acting. I learn that shock level needs to be maintained. So we rush to the store to purchase insane amounts of bleach. We start treating the pool immediately, running the polaris all during treatment. I used the pool calculator to determine the amount of bleach that needs to be used starting from a 0 reading.

Long story short, it has been 2.5 days of trying to get this under control with bleach and I’m just not sure I’m doing things the right way or if it is working. It’s a full time job trying to maintain and I am waiting on the proper tools (a proper kit that can read over 10 in total chlorine as opposed to these strips). Over the course of the last couple of days, we have put in between 20-30 gallons of bleach. I guess the algae/sun is eating it all up because a couple of hours after putting in the recommended amount of bleach to bring it up to 24, the chlorine goes down to the 5-6 level. Overnight, it goes down to 2! We have scrubbed the walls &floor. The water is crystal clear but some black spots remain. The mustard algae seems to be visibly gone, but something is consuming the chlorine! From what I understand, SLAMMING isn’t complete until there is less than 1 ppm lost overnight. Well, we put in bleach last night and woke up this morning to an FC reading of 2!

I just need to know if I am on the right track or if I am doing something wrong? Do I need to address this high phosphate reading? Continue to shock/slam? Do I need to discontinue until I get the right test kit rather than these strips that only test to an FC reading of 10?

To add insult to injury, the Pentair IC-40 is coming up on its age. The “cell” light blinks green which tells me it either needs to be cleaned or is no longer functioning. From what I understand, either way, it is not producing chlorine. I plan to acid wash it later this evening. But I don’t know if that has anything to do with what’s going on? Should I even have the salt cell on while SLAMMING?

As side note and to add more confusion to my already jumbled brain, I went to Leslie’s today to pick up the Pentair Salt Cell cleaning kit (which is essentially just a stand to acid wash the cell), I ask the guy if they have something that I can test my FC above 10 and he tells me anything above an FC of 10 is DANGEROUS and I should never read above that and I need to get it down to between 1-3. MY BRAIN IS ABOUT TO EXPLODE!!!!

Please help! I need guidance! My husband has started a new job and can’t help much with this so I’m feeling mighty overwhelmed. I’m self employed which is great because I can be home intermittently throughout the day but I need to get back to work rather than focusing 100% of my time to this pool!

Or, am I better off calling a pro on this?

Thanks so much in advance!
 
keep doing what you are doing with the bleach, brush and rake as much as you can, and post a full set of results once you get one of the recommended test kits, which can measure FC over 10. "dangerous" chlorine level is entirely dependent on the CYA level. Re-read the ABCs of chemistry and the SLAM article, all up at the top of the page, while you wait for your kit.

Either you have no CYA, a crazy amount of algae, ammonia, or some combination. Pool store results are not reliable, it's possible your CYA level is much higher. or lower!

Don't get frustrated, it could take weeks to clear up, but we will help you clear it up.


Lastly...don't go into the pool store for anything. Just don't.
 
Do not listen to the pool store people. Funny, Leslie's sell the Taylor K-2006 kits that has the FAS-DPD tests. You really need to get the kits this site suggests. Do not be running your SWG pump while slamming. I am slamming right now too. We just need to work through it. :)
 
TFTestkits.net has put together a fabulous test kit with everything you need to test your pool and get *accurate* tests. The TF-100 kit provides the best quantity of reagents for the tests you'll be doing most often.
Pool Stores are notorious for getting it wrong... such as they did with your CH testing at Leslies. How could it change like that without the addition of calcium?? 'nuff said.

TF-100, speed stir device if you've got a little extra to spend and you WILL thank us. Seriously. We can help you get that pool clean.

Oh yeah.... see if you can take back to Leslies any of those potions. We don't recommend most of them.

TFTestkits.net
 
Hi, welcome to TFP! The pool store clerk is woefully mis-informed. If you order your test kit from TF testkits it should arrive within a couple of days. They have very fast service! Since your water is mostly clear, you can add a jug of chlorine a day until your test kit arrives. That will keep things pretty much where they are now until you can give us results from your own testing. Keep the pump running and brush the pool daily. If you pH is still high you can use the muriatic acid to bring it down. Since you have only been at this 2.5 days don't throw in the towel yet! Feel free to ask as many questions as you need, and we will do our best to provide answers. We are all pool owners and have been where you are now at one point.
 
Its something that gets debated with both sides having good points.

Yes, it helps keep the FC up during a SLAM, but it can also mask the drop in FC that helps show how the SLAM is progressing. It is already paid for FC of course, but it also deducts hours from the lifespan of the SWG.

So its your call, of course, but no matter what you decide to do- ALWAYS have the SWG turned OFF during the OCLT.
 
Wow! Thank you all so much for your responses! What a helpful community of people. Rather than feeling freaked out by the people at Leslie's (who were all over the place), I feel a little more steady & reassured after reading the responses here! So thank you!

Okay, the TF-100 kit with speed stir was ordered last night. In the meantime, I will continue to add bleach to keep the FC up. I added a little less chlorine last night to see how it would hold overnight. I had been adding several times throughout the day and then right before bed I would add enough to bring it up to 24. Last night, instead of adding before bed, I tested it right before and it was at 10 (I had added 3 gallons about 6 hours prior at dusk to bring it up to 24 as per the calculator). I wanted to measure the loss overnight so I decided to forego adding bleach and I figured since Zea3 recommended only adding a jug a day until the kit arrived, it would be fine. When I woke this morning, the level had dropped to about a 1 (strip test). So I added 3 jugs this morning to try to combat this crazy heat/sun/algae/whatever it is!

As for scrubbing, I have been diligently scrubbing the walls/floor. We have both a nylon-ish brush and a metal brush (I'm guessing stainless but it looks a little corroded now). I've honestly worn out the metal brush but I feel as if I am getting most if not all of the black algae. When my husband came home last night, he was shocked that he could not see any of the spots at first glance. Now, after reading about making sure to scrub all of the nooks and crevices, I scrubbed around the two light fixtures where I hadn't even noticed any build-up and quite a bit of gunk came off in chunks. I scooped up some of the debris with a net and sure enough, it was green around the edges. I didn't even have to smear it on a paper towel to see if it was green. Now I'm thinking I'll need to hop in the water to figure out how to remove the light fixture to scrub inside the cavities. My question is:

-Is it safe to immerse myself in the water at high chlorine levels or should I wait until the level drops to a lower FC?

I guess I hadn't thought of the fact that I could have an ammonia problem - I figured it was definitely the algae considering Leslie's said my CYA was at 60 both times they tested (I'm interested to see how my own testing turns out to see if it was even close to accurate). Question:

-How do I test for ammonia or is that something I should hold off on?

On the SWG, I was so busy at keeping the pool fed and scrubbed yesterday that I didn't have a chance to clean the Pentair IC-40 to see if I could get it working. I am doing that today - first by a hose wash followed by an acid wash if necessary. I'm almost positive we will need a new one due to age even though the expenditure showing the used life of the cell only shows at 60%. Its difficult to narrow down when it was installed as it was installed a couple of owners ago, but I believe it is 4-5 years old. Questions:

-Should I replace with another IC-40 so that it can simply be dropped in?

-Another question that I have is regarding the ability to turn it off for whatever reason I need to (for instance during the OCLT). There doesn't seem to be a button/switch to power it off - it seems to be connected to the pump? Do I simply decrease the output so that none of the percentages (20%-100%) light up so that it isn't producing chlorine?

-The IC-40 manual reads "do not add any pool water balancing chemicals (including salt) unless IntelliChlor is switched off." Again, is that just a matter of decreasing the output level to 0% or do I have the unplug the thing somehow?

-How long should I keep it off when adding "water balancing chemicals"?


I will follow all of your instructions about staying away from the pool store! However, I may stop in one last time to try to return some of these unused potions since you guys don't recommend most of them. This may be answered in the ABC's of Chemistry (I've read and re-read how to SLAM), and I'm about to dive into reading the ABC's so I apologize if that is covered, but my question is:

-What sort of pool additives are recommended by this community? Where do you buy them - at a place like Lowe's rather than the pool store?

Again, thank you all SO MUCH for guiding me along. Your input is truly appreciated!
 
It isn't ammonia- ammonia would eat up every bit of your chlorine additions in *minutes*.

Turn your SWG to 0%

Buy bleach (and IF needed Borax) from H.E.B. or Walmart.

You can buy CYA (when needed) from Walmart or Lowes.

Muriatic Acid comes from Lowes in the paint department.

Baking Soda in large bags comes from Walmart or Costco.
 
You can buy chlorine at Walmart, Lowe's, Home Depot - anywhere that sells regular bleach (do not use unscented scented and splashless).

I get my muratic acid at our local hardware store. You can get it Lowe's, Walmart, Home Depot. It is usually with paint supplies.

Borax and Baking Soda can be purchased at Walmart, grocery stores, etc. (I have not had to purchase these yet.)
 
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You can buy chlorine at Walmart, Lowe's, Home Depot - anywhere that sells regular bleach (do not use unscented and splashless).

I get my muratic acid at our local hardware store. You can get it Lowe's, Walmart, Home Depot. It is usually with paint supplies.

Borax and Baking Soda can be purchased at Walmart, grocery stores, etc. (I have not had to purchase these yet.)

I think VinDeeLoo meant to say do not use SCENTED or splashless bleach!
 
Hi all! I just wanted to drop in with an update while I am waiting for the TF-100 with speed stir (estimated to arrive on Monday). I have been adding about 6 gallons of bleach a day. In the morning around 8am and in the evening around 8pm, I add 3 gallons each time which, according to the calculator, should bring it close to an FC reading of 24. I have noticed that the chlorine is holding a little bit better than it was several days ago. Still using the test strips, yesterday morning the FC read around 3 and then this morning it read at about 5.

I have a new Intellichlor IC-40 on order that is also supposed to arrive on Monday. I cleaned the existing IC-40 with a garden hose and then also with an acid wash (there was no bubbling indicating that it didn't need to be cleaned) and after reinstall the flashing green light remains. This morning, the IC-40 is also flashing "high salt". Do you guys recommend a salt testing kit/strips? Should I do anything about this "high salt" error or should I wait until the new IC-40 arrives along with the TF-100?

Before posting, I had read and re-read the SLAM article and a couple of days ago, I read the "ABC's". I learned that phosphate levels really don't matter if you have the proper amount of chlorine but that lowering phosphate levels can assist in keeping algae in check. Would there be a benefit to using the PhosFree that I already have on hand (but have never used)?

Again, thanks so much for the help & I hope you all have a lovely weekend!
 
stick with these guys here! They will get you clean the right way!

I have only been to the pool store a few times for misc small parts I needed same day and both times was amazed at the amount of stuff they sell people! Watching them test is irritating as I can only imagine the cross contamination since they are flying through it just to get some numbers so they can move on to the next person in line.
 
Hi all! I just wanted to drop in with an update while I am waiting for the TF-100 with speed stir (estimated to arrive on Monday). I have been adding about 6 gallons of bleach a day. In the morning around 8am and in the evening around 8pm, I add 3 gallons each time which, according to the calculator, should bring it close to an FC reading of 24. I have noticed that the chlorine is holding a little bit better than it was several days ago. Still using the test strips, yesterday morning the FC read around 3 and then this morning it read at about 5.

I have a new Intellichlor IC-40 on order that is also supposed to arrive on Monday. I cleaned the existing IC-40 with a garden hose and then also with an acid wash (there was no bubbling indicating that it didn't need to be cleaned) and after reinstall the flashing green light remains. This morning, the IC-40 is also flashing "high salt". Do you guys recommend a salt testing kit/strips? Should I do anything about this "high salt" error or should I wait until the new IC-40 arrives along with the TF-100?

Before posting, I had read and re-read the SLAM article and a couple of days ago, I read the "ABC's". I learned that phosphate levels really don't matter if you have the proper amount of chlorine but that lowering phosphate levels can assist in keeping algae in check. Would there be a benefit to using the PhosFree that I already have on hand (but have never used)?

Again, thanks so much for the help & I hope you all have a lovely weekend!

I'd hold off to make any more changes- you're not facing algae bloom and you probably could just maintain your FC using guesstrips reading the same level. As SLAM progresses you should see FC demand lowering and you would put less and less chlorine in the pool while getting the same FC reading using strips. Without test kit it would be difficult to see it it's over or not so just hang in there. The rest of parameters: pH, salt, phosphates, whatever can wait until you done with SLAM or you'll confuse yourself. Pool care is a slow business :).
 
Hi All,

I have a question regarding SLAMMING and inclement weather. The pool is holding chlorine better & better. It's hard to determine using strips alone, but I think I only lost 1-2 off my FC reading overnight last night (if that). The last time I put bleach in was Saturday night - and only 2.5 gallons. Today it's still reading an FC of 4-5. I'm still waiting on the TF-100 to come in today (which hopefully will still be delivered by this evening). The thing is, the rain started yesterday, has been pretty heavy today and then the forecast calls for 80-90% the rest of the week. I know I need to keep chlorine levels up to combat an algae bloom, but should I proceed with the SLAM once the test kit arrives? Will the rain water adversely affect the SLAM?

The new Pentair IC-40 came in today (but I can't install in the rain). One thing after another it seems!

Thanks again!
 
TF-100 arrived this evening. I may be a beginner with little knowledge of what I am doing, but I feel that the CYA test is pretty telling. Here were my results a few hours after putting in 3 gallons of bleach this afternoon (that should have brought it to around 24 according to the last strip test reading):

FC: 15
CC: 1
CYA: less than 20

Is the CYA reading affected by SLAMMING or high levels of chlorine (which I've been doing)? Even though Leslie's readings said we had CYA of 60 BOTH times we had it read, it seems that the CYA is MUCH lower. Granted, I did the test after dark since it arrived late, but I did the test indoors in my dining room...twice. I filled the bottle to the bottom of the label with pool water, then to the top of the label with the mixture provided for CYA. I shook it vigorously for a few seconds, waited 30-40 seconds, then shook again and dispensed the mixture into the CYA tube with the black dot. I could see the black dot all the way up to the top of the tube both times so the CYA may be close to non-existant which I'm guessing is the source of the problem (in addition to the fact that our salt cell doesn't seem to be working)?

I do have a question on the Chlorine testing. The instructions say to drop the mixture into the pink water until the water is "completely clear". I ran the test twice because I wasn't too sure about the clarity. The lighting in our dining room is not the best, but the water never really went back to "completely clear". It wasn't pink anymore but it had a little muddy tint to it even after dispensing several drops after the pink tint went away. Is that normal?

Thanks in advance for any help!
 
TF-100 arrived this evening. I may be a beginner with little knowledge of what I am doing, but I feel that the CYA test is pretty telling. Here were my results a few hours after putting in 3 gallons of bleach this afternoon (that should have brought it to around 24 according to the last strip test reading):

FC: 15
CC: 1
CYA: less than 20

Is the CYA reading affected by SLAMMING or high levels of chlorine (which I've been doing)? Even though Leslie's readings said we had CYA of 60 BOTH times we had it read, it seems that the CYA is MUCH lower. Granted, I did the test after dark since it arrived late, but I did the test indoors in my dining room...twice. I filled the bottle to the bottom of the label with pool water, then to the top of the label with the mixture provided for CYA. I shook it vigorously for a few seconds, waited 30-40 seconds, then shook again and dispensed the mixture into the CYA tube with the black dot. I could see the black dot all the way up to the top of the tube both times so the CYA may be close to non-existant which I'm guessing is the source of the problem (in addition to the fact that our salt cell doesn't seem to be working)?

I do have a question on the Chlorine testing. The instructions say to drop the mixture into the pink water until the water is "completely clear". I ran the test twice because I wasn't too sure about the clarity. The lighting in our dining room is not the best, but the water never really went back to "completely clear". It wasn't pink anymore but it had a little muddy tint to it even after dispensing several drops after the pink tint went away. Is that normal?

Thanks in advance for any help!

SLAM or chlorine have very little effect on CYA, we all wish it was otherwise. If you drained the pool due to rain you also drained CYA with it so that could explain low reading. I'd retest under sunlight as recommended and if it proves to be that low- add 56 oz of granular CYA first (about +30 ppm) and if after 24 hrs after being fully dissolved CYA level is still too low- add some more. CYA is hard to get rid of so add it slowly when you're 100% sure you need it.

They should've said 'colorless' instead of 'completely clear', mine does the same thing, it's normal. BTW, your FC level is above SLAM shock level atm, please don't add more bleach until it naturally falls down to 10 ppm, higher level just wastes chlorine and makes pool water harsh on the skin if you decide to swim in it.
 
Wait for a patch of sun to come out and re-do the CYA test with the sun to your back outdoors. I suspect it will still read lower than the Leslies test, but I am not sure by how much. The CYA test is the one test that really is lighting dependent for getting good results. You should also have a small bottle of 50 ppm CYA reference fluid that you can compare to your test results to help narrow down the actual range. Also for future reference the CYA test is somewhat temperature dependant, and the water needs to be around typical swim (room) temperature, CYA will tend to read low in cold (winter) water..
 

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