DrAchoo Posted July 24, 2012 Report Share Posted July 24, 2012 I'm changing water in my 400 gallon tub for the first time. I have followed the Bromine for Beginners but am having trouble getting the Bromine to spike after adding bleach. I used 2 oz of sodium bromide for the reserve and started with 8 oz of bleach. I didn't get a reading at all. I added another 8 oz bleach and am at about 2 ppm. This is probably about 1 hour later. pH is 7.5. TA is 80+. Hardness is 200. Recommendations? Am I doing something wrong? Quote Link to comment Share on other sites More sharing options...
waterbear Posted July 25, 2012 Report Share Posted July 25, 2012 Are you sure the product you added is all sodium bromide and not a 'one step' bromine granule (which is mostly dichlor)? How are you testing your water? If you are using a DPD test or certain strips it could be bleaching out. Even without sodium bromide in the water 8 oz of bleach should give a reading unless the test is bleaching out or you have a large sanitizer demand going on. Quote Link to comment Share on other sites More sharing options...
DrAchoo Posted July 26, 2012 Author Report Share Posted July 26, 2012 I am definitely using a sodium bromide product (99% sodium bromide on the active ingredients). I keep adding 8 oz of bleach (probably added a total of 32 oz over 48-72 hours). I've gotten a reading as high as 4 ppm, but it drops quickly back to the 1 range. To me it seems like something is eating it up. I'm not sure where to look for that source. I'm going to retry cleaning the filter, but it wasn't particular dirty to the eye. I am using the OTO drop test. I added a drop of bleach to the test container once to see what a super-high concentration would look like and it went orange not colorless. Any other suggestions? Quote Link to comment Share on other sites More sharing options...
arches2 Posted July 26, 2012 Report Share Posted July 26, 2012 i have the same thing going on. When i first filled my tub in may i could shock with bleach and get an immediate spike in bromine levels to over 10-15. Recently I've been shocking and only getting to 4-6 ppm on the bromine. It's the same bottle of bleach and i've left it out on the deck in full sun all summer. Can that affect the bleach even though the bottle is white? I've maintained a good bromine level the whole fill. the only thing i can think of is maybe i've spashed out a little too much of my bromide bank, but I've only had to top off the tub a few times, maybe 50 gallons total. Quote Link to comment Share on other sites More sharing options...
DrAchoo Posted July 26, 2012 Author Report Share Posted July 26, 2012 I soaked my filter in TSP and gave it a good hosing. Then I put 8 more oz of bleach into the tub and still only got a bump to 2 ppm. Thinking about it more I'm not sure it's actually being eaten up. I would imagine I would get a spike that would quickly disappear rather than no spike at all. I check for the spike maybe 15 minutes later and an hour and a few hours not knowing the exact kinetics, but I have never seen more than 4 ppm. I do have a spa frog and I have been reading on the controversy of whether the silver is helpful or not, but that couldn't be a cause for no spike, correct? Quote Link to comment Share on other sites More sharing options...
DrAchoo Posted July 29, 2012 Author Report Share Posted July 29, 2012 Just as an update, I believe I discovered my problem. Old bleach. I ran out of the old bottle and bought a new one. Because 8 oz hadn't been budging the bromine levels I started with 16 oz of the new bleach. It shot the levels far past 10 ppm. I've bubbled it down closer to 10 and will check it in the AM. Quote Link to comment Share on other sites More sharing options...
arches2 Posted July 30, 2012 Report Share Posted July 30, 2012 Good to know. i just finished off my bottle on Friday, so i've got a new one ready to go. I'll keep it inside this time. Quote Link to comment Share on other sites More sharing options...
waterbear Posted July 30, 2012 Report Share Posted July 30, 2012 Bleach will lose strength if stored improperly. Keep it in a cool, dark place and if it is mre than about 4-6 months old realize that you might need more than when it is fresh. This is the same whether you use it in the pool, spa, or wash. Quote Link to comment Share on other sites More sharing options...
bajabill Posted August 1, 2012 Report Share Posted August 1, 2012 I think my bleach bottles are probably weak also. Store one outside by the tub and we have been going to 105 fairly often. My next bottle is in the garage and that place is very hot also. I am using about 8 - 12 ounces after each soak and am able to keep up with the bather load. Using 3 - 6 ounces and all I could typically measure was CC and just a slight trace of FC. Anyhow, bleach is cheap, but on the flip side I dont think my heater is seeing much service. Quote Link to comment Share on other sites More sharing options...
chem geek Posted August 2, 2012 Report Share Posted August 2, 2012 Even the best 6% bleach will lose half of its strength in less than 6 months at 100ºF. It's very temperature dependent with the loss rate roughly doubling every 10ºF (yes, ºF, not ºC -- the loss rate is very temperature dependent). See the table at the bottom of this link though you have to extrapolate. Quote Link to comment Share on other sites More sharing options...
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