Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 15 of 15

Thread: Draining bromine spa into chlorine pool - bad idea?

  1. Back To Top    #1

    Draining bromine spa into chlorine pool - bad idea?

    I'm probably being laughed at for even asking this question, but I was just curious. When the time comes to change our spa water, is it a bad idea to drain it into our chlorine (BBB) pool? Will the left over bromine eat up my pools chlorine?
    Wes
    1) In-Ground pool with vinyl liner
    - ~25,000 gallons
    - Sand Filter
    - 1 HP pump
    - BBB method working perfectly since 2010
    2) Four Winds Honolulu Spa
    - ~450 gallons
    - 3 step bromine

  2. Back To Top    #2
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Draining bromine spa into chlorine pool - bad idea?

    Don't do it. Once you put bromine in the pool you have a bromine pool, which is somewhat more expensive to maintain. The only way to go back to a chlorine pool is to replace 100% of the water.
    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

  3. Back To Top    #3

    Draining bromine spa into chlorine pool - bad idea?

    Quote Originally Posted by JasonLion
    Don't do it. Once you put bromine in the pool you have a bromine pool, which is somewhat more expensive to maintain. The only way to go back to a chlorine pool is to replace 100% of the water.
    Ok, so I get not to do it, but wouldn't there be an alternative to draining 100% of the water? Couldn't you just add enough chlorine to burn up the bromine bank that you added from the spa water, then be back to a chlorinated pool? I mean, a bromine bank isn't forever lasting, is it?
    Wes
    1) In-Ground pool with vinyl liner
    - ~25,000 gallons
    - Sand Filter
    - 1 HP pump
    - BBB method working perfectly since 2010
    2) Four Winds Honolulu Spa
    - ~450 gallons
    - 3 step bromine

  4. Back To Top    #4
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Draining bromine spa into chlorine pool - bad idea?

    Bromine doesn't "burn up". It breaks down slowly over something like twenty years. There is no practical way to get rid of it other than 100% water replacement.
    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

  5. Back To Top    #5
    Patrick_B's Avatar
    Join Date
    Jun 2011
    Location
    Midland TX
    Posts
    15,001

    Re: Draining bromine spa into chlorine pool - bad idea?

    Quote Originally Posted by JasonLion
    Don't do it. Once you put bromine in the pool you have a bromine pool, which is somewhat more expensive to maintain. The only way to go back to a chlorine pool is to replace 100% of the water.
    Jason,
    Could you expand on this? Curious what you mean. Please do not misread that I am questioning your point, just wondering what this means in practical terms. Would it mean you would continue to get false Cl2 readings? Something else?
    TFP Moderator
    Essential Links:
    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

  6. Back To Top    #6

    Draining bromine spa into chlorine pool - bad idea?

    Interesting stuff. I guess I'm a little confused about people talking about going through their "bromine bank" if their water change interval is too long.
    Wes
    1) In-Ground pool with vinyl liner
    - ~25,000 gallons
    - Sand Filter
    - 1 HP pump
    - BBB method working perfectly since 2010
    2) Four Winds Honolulu Spa
    - ~450 gallons
    - 3 step bromine

  7. Back To Top    #7
    dmanb2b's Avatar
    Join Date
    Apr 2009
    Location
    NY
    Posts
    3,728

    Re: Draining bromine spa into chlorine pool - bad idea?

    Here is a great write-up from poolsolutions.com on the subject

    http://www.poolsolutions.com/tips/once- ... -pool.html
    24'x52" AGP (13,500 Gallons), Intex SWG, (2)Solar Bear 4x20 panels, Hayward S220T Filter, 1/2hp Pentair Superflo

    Pool School, TFTestKits, Pool Calculator

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

    Re: Draining bromine spa into chlorine pool - bad idea?

    Bromine comes in two forms: bromine and bromide. Bromine is the active form that sanitizes the pool. Bromide is the inactive form that just sits in the water waiting to be reactivated. When you add chlorine the chlorine very quickly gets used up turning some of the bromide back into bromine. When the bromine gets used up from sunlight or sanitizing the pool it turns back into bromide.

    Bromine can not be stabilized against sunlight nearly as well as chlorine can be. So bromine breaks down into bromide more quickly that chlorine would (assuming you are following our recommended levels, unprotected chlorine breaks down even more quickly). That mean you end up using more chlorine to maintain a bromine pool than you would a chlorine pool.

    In a spa you can use up your bromide bank through splash out fairly quickly, because a spa is very small compared to a pool, but the amount of water carried out by a person getting out is the same in either case. In a spa, a couple of people getting in and out over a few weeks end up carrying off a fair bit of the water, reducing your levels. In a pool that is a far far slower process because there is so much more water to begin with.
    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
    Patrick_B's Avatar
    Join Date
    Jun 2011
    Location
    Midland TX
    Posts
    15,001

    Re: Draining bromine spa into chlorine pool - bad idea?

    Quote Originally Posted by dmanb2b
    Here is a great write-up from poolsolutions.com on the subject

    http://www.poolsolutions.com/tips/once- ... -pool.html
    Aaahhh. Thanks dman...I am enlightened. Appreciate it very much.
    TFP Moderator
    Essential Links:
    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

  10. Back To Top    #10
    Patrick_B's Avatar
    Join Date
    Jun 2011
    Location
    Midland TX
    Posts
    15,001

    Re: Draining bromine spa into chlorine pool - bad idea?

    Thanks Jason, I appreciate you explaining it. Enlightened further. Much appreciated.
    TFP Moderator
    Essential Links:
    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

  11. Back To Top    #11

    Draining bromine spa into chlorine pool - bad idea?

    Quote Originally Posted by Brushpup
    Thanks Jason, I appreciate you explaining it. Enlightened further. Much appreciated.
    Ditto, thanks!

    So, suppose this UNenlightened idiot (me) put about 20 gallons of brominated water into my chlorinated pool. Would that little into a 25k gallon pool make it a bromine pool now?
    Wes
    1) In-Ground pool with vinyl liner
    - ~25,000 gallons
    - Sand Filter
    - 1 HP pump
    - BBB method working perfectly since 2010
    2) Four Winds Honolulu Spa
    - ~450 gallons
    - 3 step bromine

  12. Back To Top    #12

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: Draining bromine spa into chlorine pool - bad idea?

    20 gallons in 25,000 is more than a 1000 to 1 dilution. That will probably result in a negligible bromide/bromine amount. However, it's not based on your bromine level, but your bromide bank and that could be high if you not only added sodium bromide initially but also used bromine tabs. Even so, it's probably not more than 100 ppm so after dilution into the pool would be around 0.1 ppm.

    Bromide goes away only through water dilution, similar to other salts. Bromine can outgas from the pool somewhat, though does so more slowly if you've used bromine tabs since they add DMH that acts somewhat like CYA if the concentration gets high. Bromine can form organic bromamines that may get filtered out in some cases. However, you can't really count on these methods of reduction as they could be very slow.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

  13. Back To Top    #13

    Draining bromine spa into chlorine pool - bad idea?

    Thanks for the info. Thankfully, my FC seems to be pretty stable and I'm not losing any more than usual through the day. So I think I'm safe. No more spa water into pool water action though, I promise.
    Wes
    1) In-Ground pool with vinyl liner
    - ~25,000 gallons
    - Sand Filter
    - 1 HP pump
    - BBB method working perfectly since 2010
    2) Four Winds Honolulu Spa
    - ~450 gallons
    - 3 step bromine

  14. Back To Top    #14

    Join Date
    Aug 2011
    Location
    Blanchard, Oklahoma
    Posts
    26

    Re: Draining bromine spa into chlorine pool - bad idea?

    What if you go from a bromine hot tub directly into a chlorine pool? Are you doing basically the same thing with the same consequences?
    30ft x 54in AGP 24,900 gallons
    400 lbs High Rate Sand filter
    2HP, 2 speed pump
    Pool Install April 2012

  15. Back To Top    #15

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: Draining bromine spa into chlorine pool - bad idea?

    When you say "go from" do you mean you are soaking in one and then getting out of the spa and then into the pool? Yes, it is similar except you are transferring MUCH less water when you do this -- a negligible amount.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

Posting Permissions

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