Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 18 of 18

Thread: Algae/Filter Problem - Pool guy says to go DE

  1. Back To Top    #1

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Algae/Filter Problem - Pool guy says to go DE

    I have a 23K gallon, vinyl lined, in-ground pool, with a Hayward pump and 300 lb sand filter. Water is green with algae, even though my water condition is good (pH: 7.4, Chlorine 5+, TA 100). Pump is running 24/7. Shocking every few days to try to get rid of the algae. Even changed the sand out in the filter to the zeo-sand.

    Been getting advice from a pool maintenance guy and he says that since I am maintaining balanced water, the problem is filtration and he suggests I switch to DE. That's a high dollar commitment on this pool.

    Not sure why all of a sudden the filter does not work (had the pool for 3 years and no problems, now green water for 2 summers straight). Any suggestions?

    Should I go with the DE?
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

  2. Back To Top    #2

    Join Date
    Jan 2009
    Location
    Cupertino, CA
    Posts
    1,966

    Re: Algae/Filter Problem - Pool guy says to go DE

    If the pool is still green then you're not killing the algae and switching to DE won't help. If you need to placate the guy then you can just put 1/2 lb DE in your sand filter, it will have much the same effect and be way cheaper.

    First thing, though, is to check your CYA; your chlorine level might be way too low. What kind of chlorine have you been using? If it's the tabs, or dichlor powder, then your CYA is almost certainly sky-high and you will really need to crank up the chlorine--and sooner or later you'd need to replace a lot of water to bring the CYA down.

    So, get a CYA test from the pool store, or second best get the store to test it for you.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

  3. Back To Top    #3

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Algae/Filter Problem - Pool guy says to go DE

    JT,

    Welcome to the forum. Reinforcing what Paul has said, filtering is not your issue....lack of chlorine is your issue.

    Shocking a pool to get rid of algae is not a one-time event. It is a process that kills all the algae in your pool and then the filter filters it out.

    Up in Pool School, read "ABC's of pool water chemistry", the "chlorine/CYA chart", and then "How to Shock your pool".

    You must hold your chlorine levels at shock value until your pool is crystal clear. This may take a few days. Your filter is irrelevant in this case.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  4. Back To Top    #4
    Guest

    Re: Algae/Filter Problem - Pool guy says to go DE

    You definitely need to know your CYA level and then shock to the correct value based on the pool calculator and like they said, hold that level until the FC stabilizes and does not drop.

    If you had been shocking every week and still having the issue, you should have noticed the pattern that it cleared and little and came back. That indicates it never really cleared up the algae.

  5. Back To Top    #5

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Re: Algae/Filter Problem - Pool guy says to go DE

    Well, on the recommendation of the local Leslie's Pool Supply manager I tried Green To Clean today. Raised the pH to 8, threw in 3 lbs Green to Clean and 2 lbs of Power Powder Plus shock. Gotta do the shock again at 3am (12 hours after first application) and again at 3pm tomorrow.

    So far the water has gone from solid green to aqua marine.

    As far as CYA, I do not have a way to test it and just realized that Leslie's does not test it when I bring in the water. So next time I go in, which will probably be Monday, I will ask them to test CYA and get a CYA test kit.

    I'm gonna look through Pool School and try to learn more. I thought I understood the chemistry of a pool, but obviously I still have a lot to learn.

    Question though. Let's assume that I can get the pool clear through my current actions, what's to say that I won't have a green pool after the next rain? I mean, last summer I had this same green problem and my water balance was good. So I am nervous about all of this now.
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

  6. Back To Top    #6

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Algae/Filter Problem - Pool guy says to go DE

    Question though. Let's assume that I can get the pool clear through my current actions, what's to say that I won't have a green pool after the next rain?
    Your pool will stay clear all Summer long (rain has little effect) if you will maintain adequate chlorine levels. The knowledge for that is up there in Pool School......unfortunately, it will not be found at Leslies.

    Their advice may temporarily clear up your pool but until you understand the importance of chlorine in your pool and that it must be constantly replenished, you will continue to have algae blooms.

    I would start Pool School with "The ABC's of Pool water Chemistry" and go from there.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  7. Back To Top    #7

    Join Date
    Apr 2007
    Location
    Arizona
    Posts
    924

    Re: Algae/Filter Problem - Pool guy says to go DE

    Odd, I've never known Leslie's to not test your CYA as a standard set of tests they perform. Perhaps that's just my Leslie's, well, my DD's Leslie's always tests hers, too. Could still be an Arizona thing they always do. Unless you tell them your water has an issue, they don't always test for phosphates or metals and such, though. So, are you sure they aren't testing CYA, but calling it conditioner or stabilizer instead of CYA?

    By the way, a lot of people pooh pooh Leslie's testing, but my Leslie's actually does a pretty good job of testing. Not true of some pool stores, though. Ever so often I take a sample to them to check against my test results and I have to say we are always pretty close at Leslie's. Yesterday, I got a, "Congratulations! Your pool is perfectly in balance."
    Buggs

    14,000 gallon, in ground, plaster, free form, play pool.
    Sta-Rite Max-E-Glass with a 1.5 hp Emerson motor
    WaterCo Micron High Rate sand filter S750 490 lb, 4883 sq ft - using ZeoBest
    In floor Polaris cleaning system
    Blue Diamond robot for those after storm days when I can't wait overnight for the in floor to clean it.

  8. Back To Top    #8
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Algae/Filter Problem - Pool guy says to go DE

    There are some great pool stores out there, there are also many many bad ones. The challenge is knowing which is which. Most people won't know good stores from bad, and so can't trust their local store.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  9. Back To Top    #9
    Butterfly's Avatar
    Join Date
    May 2007
    Location
    South Carolina
    Posts
    10,045

    Re: Algae/Filter Problem - Pool guy says to go DE

    Hi jtkopp,

    I'd like to add that the best investment we made in our pool is our test kit.
    The TF100 sold by duraleigh at TFTestKits.net is the best bang for the buck and they have A-1 service.
    Having your own kit will put YOU in control of your pool.

    Keeping your pool clean and sparkly is very easy thru the methods taught here.

    It would be very helpful if you added your pool & equipment specs in your sig. Go to User Control Panel (upper left under TFP logo), select Profile, then Edit sig.

    We also need test results to include:
    FC - Free Chlorine
    CC - Combined Chlorine
    pH -
    TA - Total Alkalinity
    CH - Calcium Hardness
    CYA - Cyanuric Acid (stabilizer)
    Borates - (if you are using borates)

    Welcome to the forum
    TFP Moderator TF100 Test Kit TF100 TestKit YouTube Channel PoolMath
    You're done SLAMing when:
    1)You lose 1ppm or less FC overnight, & 2)You have .5ppm CC's or less, & 3)your water is clear.

    ~ One should not use a sledge hammer to swat a mosquito. ~

    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  10. Back To Top    #10

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Re: Algae/Filter Problem - Pool guy says to go DE

    I did buy a reagent kit from Leslie's and I also take water samples into Leslie's quite frequently, especially given the problems I have been having. Here are the results from today

    FC 2
    CC 2
    pH 7.2
    TA 110
    CYA 100

    Keep in mind, I do have a sand filter, with the zeo-brite sand and a Hayward pump (with the Leslie's name on it). I have an external (not sure of the name) chlorine feeder, that I use the Leslie's brand 3" chlorine pucks (stabilized).

    So based on what I have read here, my CYA is high. We are supposed to get some afternoon/night time storms this week, so perhaps that will go down. Should I turn down my chlorine feeder?

    I will be scouring the Pool School, trying to soak up all the info I can. Last year was a nightmare for me, and this year was gearing up to be the same. As I stated when I started this thread, one of the local pool service guys was telling me to get a DE filter, and I decided against it. You all saved me $15K!!!! Thank you
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

  11. Back To Top    #11
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,965

    Re: Algae/Filter Problem - Pool guy says to go DE

    The rain won't be enough. You'll need to replace AT LEAST 40% of your pool water to lower your CYA.

    I recommend you stop using pucks tonight and start using bleach.

    Is this the kit you bought at leslies?
    http://www.lesliespool.com/browse/Ho...400000/I/18547

    or this one:
    http://www.lesliespool.com/browse/Ho...400000/I/81330

    or did you get the correct one:
    http://www.lesliespool.com/browse/Ho...400000/I/81329

    You need to look at the CYA chlorine chart - your FC level is too low for your CYA level. That's probably why you had/have problems, you don't have enough chlorine to keep algae away. Once you have algae issues, you have to shock. Shocking when your CYA is that high is problematic and a losing battle at best.

    I highly recommend you do a partial drain/refill to lower the CYA before you try to shock.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  12. Back To Top    #12

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Re: Algae/Filter Problem - Pool guy says to go DE

    After reading more on this web site about CYA and FC, I to realized what you are saying is true. My CYA is way too high and my FC is way too low.

    I just shut down my chlorine feeder, which had the trichlor pucks in it and I will be buying some gallons of liquid chlorine bleach tomorrow.

    Weird thing is that I just did a floc to the pool and through vaccuming to waste dropped the water way down, probably 1/3 and then put new water back in. I do not know what my CYA level was before that whole chore, but that was only 2 weeks ago. Can CYA build up that fast from these pucks?

    So I need to drop the water out and add new? Then worry about shock and the rest?
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

  13. Back To Top    #13
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,965

    Re: Algae/Filter Problem - Pool guy says to go DE

    No, your CYA was probably much higher.

    Yep, repeat the drain/refill/retest.

    Which kit did you buy? (This is important.)
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  14. Back To Top    #14

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Re: Algae/Filter Problem - Pool guy says to go DE

    I bought the first test kit you listed. I guess that's not the right one.

    How much water would you say to drop out of the pool and replace?

    Once I do that, then what? Retest and get pH/TA back in acceptable range and then chlorine?
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

  15. Back To Top    #15
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,965

    Re: Algae/Filter Problem - Pool guy says to go DE

    Quote Originally Posted by jtkopp
    I bought the first test kit you listed. I guess that's not the right one.

    How much water would you say to drop out of the pool and replace?

    Once I do that, then what? Retest and get pH/TA back in acceptable range and then chlorine?
    I would drain down 1/3 and refill, retest CYA, and repeat if necessary. When it's in range, then you adjust PH and begin tackling the chlorine issue.

    Your kit can't test for CYA. You'll need a CYA test kit, especially since you are adjusting the levels. I wouldn't rely on pool store testing for that - they are notorious for doing it wrong.

    Also, you need the FAS-DPD chlorine test. Taylor and TFtestkits.net both sell it seperately for about $25. IT can test FC up to 50, which you need when you have to shock. Your kit can only test up to 5.

    Hope this helps.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  16. Back To Top    #16

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Re: Algae/Filter Problem - Pool guy says to go DE

    While I agree that my CYA is high, I have been reading posts that indicate that CYA of 100 is not unheard of and not horrible (saw a post from waterbear on that). Question - can I use shock to raise the FC level to 7 and have a useable pool? I ask, because I have not had the opportunity to enjoy my pool yet this summer and don't want to spend so much more time away from that. Is there anything I can do that will allow me to enjoy my pool now and for the rest of the summer?
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

  17. Back To Top    #17

    Join Date
    Jan 2009
    Location
    Cupertino, CA
    Posts
    1,966

    Re: Algae/Filter Problem - Pool guy says to go DE

    With CYA 100, bringing FC to 7 won't kill the algae. That's a normal maintenance level for a clean pool.

    IF you have a clean pool, it's possible to run with CYA 100 and keep from having problems; but once you have a problem, it's much harder to solve.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

  18. Back To Top    #18

    Join Date
    Jun 2008
    Location
    Vienna, VA
    Posts
    15

    Re: Algae/Filter Problem - Pool guy says to go DE

    I see the dilema. This is probably why I had such a horrible time fixing the pool last year and again this year. I will drain water and refill, then retest CYA.
    In-ground, vinyl pool, full sun - 23K gallon, Leslies (Hayward) pump, Hayward 60 sq ft (300 lb) sand filter

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •