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Thread: Algae....dust?

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    Algae....dust?

    I have a 9x18x4ft deep Costco Bestway pool.

    The power went out the other day. I didn't think to check the GFCI on the pool pump. Yesterday I uncovered it for my kids, and found a sort of green dust on the bottom of the pool.

    If it is algae, how much chlorine should I use to shock it? If it's not algae what is it?



    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    Oh....this is after vacuuming the sides....

    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    How long have you had the pool? What chemicals have you been using since you filled?

    The secret to a great pool is understanding chemical balance. Please read pool school.

    Please consider getting a good test kit, either the TF100 or the K 2006. Don't waste money on anything less. You could add 1/2 jug of bleach every night until you get your kit.

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    Re: Algae....dust?

    Quote Originally Posted by SD_Rider View Post
    I have a 9x18x4ft deep Costco Bestway pool.

    The power went out the other day. I didn't think to check the GFCI on the pool pump. Yesterday I uncovered it for my kids, and found a sort of green dust on the bottom of the pool.

    If it is algae, how much chlorine should I use to shock it? If it's not algae what is it?



    Sent from my SAMSUNG-SGH-I337 using Tapatalk
    Welcome to the forum.

    That looks like algae to me.

    Algae does not form from the lack of filtration. Algae forms from the lack of sanitizer (chlorine). Your pump & filter's primary function is to circulate water, & remove particulates (dirt) from the water.

    You will need chlorine to kill the algae, but how much chlorine you need depends on how much CYA (stabilizer) is in the water.

    How have you been chlorinating and testing the pool water?

    What FC level do you normally maintain?

    Can you provide some basic test results, FC (free chlorine), pH, TA (total alkalinity) & CYA (stabilizer)?

    Please have a read through Pool School, especially The ABC's of Pool Water Chemistry, How to Chlorinate Your Pool, Definitions & Abbreviations & Chlorine-CYA Chart.

    Dom
    Dom - TFP Guide
    Intex 18' X 48" Ultra Frame AGP 6700 gallons | Two Intex CS8110 SWG's | Hayward Pro Series 21" Sandfilter | Hayward 1.5HP Power Flo Matrix pump | Hayward Thru-wall Skimmer | Wanda the Whale | 72 sq ft of Sungrabber Solar Panels with Hayward GLC-2P-A | Taylor K2006 Test Kit, Sample Sizer & Speed Stir | Click Here To Become a TFP Supporter!

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    Re: Algae....dust?

    Thanks!
    I have read Pool School and a few other threads. I'm certain it's mustard algae.
    I shocked it with

    I have the Poolmaster 5 way test kit. Amazon.com : Poolmaster 22260 5-Way Test Kit with Case - Basic Collection : Swimming Pool Liquid Test Kits : Patio, Lawn Garden
    I also supplement with the 4 Way strips...just for a quick test and use that for my jacuzzi also.
    Neither test for CYA, so I will need to expand the kit.

    FC was high, PH was low, and TA was ok. I honestly think it was the pump not being on for...I know found out...3 days and being covered up.

    I usually keep the FC high. I have a simple chlorine tab floater and test it every few days. I and/or the kids get in almost every day. I have the pump running for about 10 hrs/ day. (0900-1900)

    I used Clorox Pool Shock Xtra Blue from Lowes.
    Like this Amazon.com : Clorox Pool Garden
    I ended up using the whole thing. It says that 1lb is good for 10k gallons. I have ~4750 gallons.

    Leaving it uncovered, I vacuumed, backwashed the sand filter, and shocked it on Friday and turned the pool pump to run constantly. Friday evening, it was very cloudy, so I used the rest of the shock. I backwashed Saturday and again on Sunday. By Sunday, it was mostly clear. I think I need to shock it again, as I was vacuuming again yesterday.

    Is there a better shock to use? I'm not sold on the Clorox Xtra Blue at $4/lb.

    I'm also researching an automatic vaccuum. Any recommendations? My Bestway skimmer bucket mount has already cracked.
    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    You don't need to "shock", you need to SLAM....
    Pool School - SLAM - Shock Level And Maintain

    to do so, you need a proper test kit. One that can measure CYA, and higher chlorine levels.
    26' X 52" Intex Ultra Frame. Intex Sand Filter
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    Re: Algae....dust?

    Quote Originally Posted by SD_Rider View Post
    Thanks!
    I have read Pool School and a few other threads. I'm certain it's mustard algae.
    I shocked it with

    I have the Poolmaster 5 way test kit. Amazon.com : Poolmaster 22260 5-Way Test Kit with Case - Basic Collection : Swimming Pool Liquid Test Kits : Patio, Lawn Garden
    I also supplement with the 4 Way strips...just for a quick test and use that for my jacuzzi also.
    Neither test for CYA, so I will need to expand the kit.

    FC was high, PH was low, and TA was ok. I honestly think it was the pump not being on for...I know found out...3 days and being covered up.

    I usually keep the FC high. I have a simple chlorine tab floater and test it every few days. I and/or the kids get in almost every day. I have the pump running for about 10 hrs/ day. (0900-1900)

    I used Clorox Pool Shock Xtra Blue from Lowes.
    Like this Amazon.com : Clorox Pool Garden
    I ended up using the whole thing. It says that 1lb is good for 10k gallons. I have ~4750 gallons.

    Leaving it uncovered, I vacuumed, backwashed the sand filter, and shocked it on Friday and turned the pool pump to run constantly. Friday evening, it was very cloudy, so I used the rest of the shock. I backwashed Saturday and again on Sunday. By Sunday, it was mostly clear. I think I need to shock it again, as I was vacuuming again yesterday.

    Is there a better shock to use? I'm not sold on the Clorox Xtra Blue at $4/lb.

    I'm also researching an automatic vaccuum. Any recommendations? My Bestway skimmer bucket mount has already cracked.
    Oh my, you dumped in 24X the recommended dose (the whole box)????? Or do you mean you use a whole pound (2X dose)?

    One pound (16oz) of dichlor in your pool volume will raise the FC by 14ppm, and the CYA by 13ppm. You need to stop using that Xtra Blue, it's going to drive your CYA off the charts, if it is not already.

    Use regular bleach, 8.25% sodium hypochlorite. Plain bleach, no "ultra" or scented type. Each cup (8oz) will raise your FC by about 1ppm.

    Unfortunately, without knowing what your CYA level is I can't recommend how much chlorine to add to the pool. How many 1lb bags of the Xtra Blue have you used this season? Multiply that by 13 and we will have an educated guess on CYA level, but it is still a guess. If you have used 3 bags your CYA level would be ~40ppm, requiring a SLAM level of 16ppm, with a maintenance target of 5ppm. Throw another 1lb bag in and your CYA goes above 50ppm (~53), making SLAM level 24ppm & maintenance FC at 7ppm (rounding up to 60ppm CYA). Mustard algae would require Shock levels of 24ppm for 40ppm CYA & 34ppm for 60ppm CYA.

    If you have indeed used the entire box (12lbs) of Xtra Blue your CYA will be above 150ppm and replacing all the water would be best.

    I hope you see how important a proper test kit is. The test kit you have will only measure FC to 5ppm.

    Do you plan to truly take control of your pool, and understand exactly what it needs? You will need a proper test kit to do so.

    Your filter (or lack of) did not promote your algae issue. Improper FC/CYA levels did. While no circulation is bad for any contained body of water, if there was adequate FC and the pool was brushed each day algae could not grow.

    Your filter is there to remove dirt and anything the chlorine kills.

    Dom
    Dom - TFP Guide
    Intex 18' X 48" Ultra Frame AGP 6700 gallons | Two Intex CS8110 SWG's | Hayward Pro Series 21" Sandfilter | Hayward 1.5HP Power Flo Matrix pump | Hayward Thru-wall Skimmer | Wanda the Whale | 72 sq ft of Sungrabber Solar Panels with Hayward GLC-2P-A | Taylor K2006 Test Kit, Sample Sizer & Speed Stir | Click Here To Become a TFP Supporter!

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    Re: Algae....dust?

    Thanks for your inputs.

    I'm ordering a better test kit so I can test CYA levels and get on track.

    Admittedly, I'm a noob and was a bit impatient with results. I got worried with what I read about algae. Just the 1lb, so 2X what was needed.

    Looking at the different kits, will I be able to use the reagents in my current kit for the new ones or are they completely different? Looks like there's alot of discussion regarding FAS/DPD and OTO tests. Most seem to prefer the FAS/DFD, so I'm looking at the Taylor 2006.
    Amazon.com : TAYLOR TECHNOLOGIES INC K-2006 TEST KIT COMP CHLORINE FAS-DPD : Swimming Pool Liquid Test Kits : Patio, Lawn Garden

    Dom, my skimmer clamp just broke so currently my input is going through my vacuum at the bottom of the pool. Thanks for the link.
    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    The FAS/DPD is the test you need. I have the K2006, it's a great kit but the amount of FC & CYA reagent will go quick, especially during a SLAM with higher CYA.

    The TF-100 with XL option is the better option. You should have enough reagents to make it through the SLAM, the rest of the season, and probably spring opening.

    If I had known of the TF-100 when I bought my kit, I would have bought the TF-100 instead.

    Be sure to read up on the SLAM procedure, and start hunting for good bleach/chlorine deals.

    Dom

    - - - Updated - - -

    Be sure to get your pump/filter running well, it will be going 24/7 throughout the SLAM

    If your pool is filled to 42" you will have a volume of about 4200 gallons. With that, 6.5 oz of 8.25% bleach will raise FC by about 1ppm.
    Dom - TFP Guide
    Intex 18' X 48" Ultra Frame AGP 6700 gallons | Two Intex CS8110 SWG's | Hayward Pro Series 21" Sandfilter | Hayward 1.5HP Power Flo Matrix pump | Hayward Thru-wall Skimmer | Wanda the Whale | 72 sq ft of Sungrabber Solar Panels with Hayward GLC-2P-A | Taylor K2006 Test Kit, Sample Sizer & Speed Stir | Click Here To Become a TFP Supporter!

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    Re: Algae....dust?

    Quote Originally Posted by domct203 View Post

    Use regular bleach, 8.25% sodium hypochlorite. Plain bleach, no "ultra" or scented type. Each cup (8oz) will raise your FC by about 1ppm.
    You can use "Ultra" bleach... it's the best kind, actually. It has 8.25% Sodium Hypochlorite. The only scent you want is regular scent-- which is really no scent added. (They call it regular scent because it was the original "scent" before they started adding all the fancy "flavors", as I call them: rainforest, mountain breeze, etc.) It will most likely be in a jug that holds a little less than 3.8 quarts... so not quite a gallon. Keep that in mind when figuring out how much you are adding.

    Alternatively you can get Liquid Chlorine from the pool store (where it may be up to 12.5%-- be sure to ask) or from Walmart in the hardware/ garden department (Wally LC has 10% Sodium Hypo.) The LC is sold in full gallons. Again, important to know when you are figuring out how much to add.

    You will want to check the label on the Clorox shock you used... many of them now contain copper as a "bonus" algaecide.

    Copper is effective as an algecide (or really an algaestat, it prevents new growth) but it is actually copper in pool water that turns hair and fingernails green, NOT chlorine as most people believe. Copper does not break down over time, and so will stay in your pool until it gets diluted from adding new water after back-washing the filter. (Refilling to make up for evaporated water does not contribute to dilution)

    If you overdosed your pool with a product that contains copper, you will probably want to consider draining your pool and refilling, before you spend a lot of money feeding it chlorine... only to decide later that you need to start over with new water because of the copper.

    Either way, you need a good kit.

    The TF-100 from tftestkits.net is the best bang for your buck. It was custom designed by the owner of the TFP site, so it has the reagents sized according to how they are used most frequently-- you get more of the ones that usually run out first.

    The regular K-2006, is a fine kit... but the reagent bottles that come in it are all the same size: only 22 ml each (3/4 oz) and you will use about 1 - 1.5 ml (or more) of one of the chlorine reagents (the R-0871 liquid) each time you test your FC level, and ideally you need to test several times a day during a SLAM. Twice a day is the bare minimum... but the more often you test and re-dose back up to SLAM level, then the faster your pool will clear up and be safe and sanitary. So that means you could run out of reagent for the FC test in just 2 or 3 days.

    The TF-100 with the XL option that was recommended by another poster, will give you twice as much DPD-FAS powder as the K-2006 has, and almost 6 times the main Cl reagent (120 ml total). All of the "chemistry" in the TF-100 is identical to the K-2006, just more of it.

    And as a bonus, a purchase from tftestkits.net, helps to support the forums. If you become a "site supporter" (link at top of page) you will get a discount on the kit. But it's a great value even without the discount. I wish I had done more research when I bought my K-2006.

    (And as far as being able to use your current kit after you get the recommended one... the answer is yes, you will be able to use up most of it for your daily maintenance checks, if you want to... but I think you'll find the quality of the Taylor reagents will spoil you, and the kit you have now will seem hard to read in comparison.)

    BTW, you mentioned that you were scared after reading about algae...
    Algae won't hurt you. But if all your Cl is getting used up to fight algae... then you don't have any FC to kill pathogens (bacteria and viruses, especially fecal germs-- because everyone who gets in the pool brings their bottom with them )

    I am also curious why you think you have mustard algae. It looked to me like your pool is in full sun. Mustard algae generally grows in shady areas of the pool: in the corners, behind the ladder, under the steps, etc. And it's called mustard algae because it is quite yellow... definitely not green. Your pics show a very green pool...
    So my vote is that you have plain ol', regular, garden-variety algae... not Mustard Algae.

    That's a good thing.


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    Re: Algae....dust?

    Thanks for all the good info.
    It was powdery on the bottom edges of the pool. I vacuumed more over the last few days and it's all clear again.

    Question: I've backwashed a few times. How often do I need to replace or top off the sand in the sand filter? Drain and check level?

    I already ordered the K2006. Just waiting for it to arrive.

    I plan to run the pool year round. I may need to invest in an electric water heater. I have solar now, so the energy bill is not a concern.
    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    As long as your filter is working properly the sand should not need replenished. Occasionally a deep clean of the sand can get rid of anything that didn't come out backwashing.

    Deep Cleaning a Sand Filter

    Once you get your test kit, test and report back the results. I would recommend performing an OCLT (overnight chlorine loss test) to see if you need to SLAM.
    26' X 52" Intex Ultra Frame. Intex Sand Filter
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    You can lead a horse to (clear) water, but you can't force him to swim in it!

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    Re: Algae....dust?

    Thanks!
    Once I get the algae cleaned up, I'll clean the sand filter.

    I'm a maroon. I put the Taylor kit in my Amazon cart and didn't check out.
    After looking around this morning, I found the TF-100 test at poolworldsupply.com for $68 and free shipping. And they have a location here in CA, so hopefully I'll get it in a day or 2.
    I looked at tfttestkits.com, but at the same price, they wanted $20 shipping.

    Went and looked at the pool....after a couple of hot days, it got worse. Still has a chlorine tab floating.

    Should I be covering it up daily?
    Last edited by SD_Rider; 09-02-2015 at 09:13 AM. Reason: adding
    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    You should really just use a little bleach every day rather than using the pucks until your kit arrives.

    You can cover it if you want. Covers can protect FC depending on the type of cover you have. It can also harbor algae. Regardless, always let your pool breathe without the cover at least 2 hours a day.

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    Re: Algae....dust?

    Is that to keep the CYA out of the pool?

    I found out that the TF100 kit doesn't arrive til Tuesday, so ordered the 7way testing strips. (Amazon 1 day = free).
    TH - 250
    TC - 10
    FC - 10/20
    PH - 7.8 (I measured 7.2 with my kit.)
    TA - 180
    CA - between 150/300....color is close.

    With the man-made drought....I didn't want to drain 75% of my pool.

    Can I get my CA level down without drain/refill?
    Probably easier, but I have more time than money and prefer to treat as much as possible. Worried about a fine if I drop 2-3k gallons of water.

    Leaving the cover off, I've lost alot of water already, so I will have to remeasure for total gallons. Good news is that the Hayward skimmer arrived, so I'll need to drain part of the pool anywho.

    I also vacuumed out the algae yesterday and today....as soon as it settles, I vacuum right away.
    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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    Re: Algae....dust?

    Yup. Pucks add CYA.

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    Re: Algae....dust?

    "A little bleach". How much? I'm at 33" deep. 9x18x3 = 3600 gallons.

    Weird thing this morning. I have algae sitting on the bottom of the pool. When I vacuum, it comes right through the filter. I can visibly see the cloud at the intake to the pool (like an oil leak cloud).

    I'm trying to lower the pH. It was at 7.8 this morning. Pool math said to add 3.5 oz of Muriatic acid. How long before remeasuring? 1000gal/hr pool pump...so 3.5 hours?
    Costco Bestway AG Pool 9x18x4. (Installed July 2015) 4500 gallons
    Intex 2800 GPH Pump & Sand filter
    TF 100 Test Kit
    335 Gallon Jacuzzi

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