mgrobins Posted October 7, 2009 Report Share Posted October 7, 2009 Hi, I am a regular reader of the forum and have a need for some advice so I joined up to post . I have a fiberglass 2100L spa that I maintain with an ozonator (just replaced), N2 stick and lithium or MPS in low doses. The cost of the lithium and MPS is an ongoing expense that I hoped to reduce by switching to bleach. I have added an amount of CYA which I acquired from my pool shop (doesn't disolve well does it!), and measured using the pool calc. When I add the liquid bleach (White King 6% regular) I notice some "fizzing" and this evening I added 25ml before bathing and the spa foamed up heavilly. Do bleaches have a detergent or additives which will influence foaming? The water chem is roughly: pH 7.6 TA: 50 CH: 40 ... (very soft water in my area - have run out of calcium but never had dramas with a low amount). The water has only been recently replaced (about a week ago). I considered it may be low pH or TA that are at cause but having changed sanitizer I thought I'd investigate. Another query is borates. I use "spa silk" which is boric acid. Same thing? Is this just a weak acid that acts as a buffer? What impact is there of having more or less? Thanks for all the useful posts and any advice people can offer for my queries . Mick Quote Link to comment Share on other sites More sharing options...
bart6453 Posted October 7, 2009 Report Share Posted October 7, 2009 Hi, I am a regular reader of the forum and have a need for some advice so I joined up to post . I have a fiberglass 2100L spa that I maintain with an ozonator (just replaced), N2 stick and lithium or MPS in low doses. The cost of the lithium and MPS is an ongoing expense that I hoped to reduce by switching to bleach. I have added an amount of CYA which I acquired from my pool shop (doesn't disolve well does it!), and measured using the pool calc. When I add the liquid bleach (White King 6% regular) I notice some "fizzing" and this evening I added 25ml before bathing and the spa foamed up heavilly. Do bleaches have a detergent or additives which will influence foaming? The water chem is roughly: pH 7.6 TA: 50 CH: 40 ... (very soft water in my area - have run out of calcium but never had dramas with a low amount). The water has only been recently replaced (about a week ago). I considered it may be low pH or TA that are at cause but having changed sanitizer I thought I'd investigate. Another query is borates. I use "spa silk" which is boric acid. Same thing? Is this just a weak acid that acts as a buffer? What impact is there of having more or less? Thanks for all the useful posts and any advice people can offer for my queries . Mick Hmm....did you use their "power clean" product, the concentrated, or the regular bleach. After a quick look at their sight, they do not have MSDS information available and many different products that look very similar. There might be a surfactant/detergent in some of their products. Just an idea, chem geek or nitro may have a bit more insight than I do. Quote Link to comment Share on other sites More sharing options...
chem geek Posted October 7, 2009 Report Share Posted October 7, 2009 Mick, It's possible that the White King brand may have some additives causing the problem. Clorox Regular (6%) has minimal additives and also the lowest amount of excess lye. You might try it instead. Also, to reduce foaming in general (independent of sanitizer), you should raise your Calcium Hardness (CH) to around 120 ppm though in your case with the low TA you can raise it higher to at least 150 (even 200 ppm is fine given your low TA). Yes, boric acid is the close-to-pH-neutral form of borates. Assuming this product is pure boric acid (check the ingredients for purity), you would add about 13 ounces weight or around 15 ounces volume (just shy of 2 cups) to get to 50 ppm borates. Yes, pure CYA doesn't dissolve quickly which is one reason why it's easiest to just use Dichlor initially to build up the CYA. By the way, if you were using lithium hypochlorite without any CYA in the water, then the active chlorine level in your spa was very high. The chlorine probably dissipated more quickly as well. Richard Quote Link to comment Share on other sites More sharing options...
mgrobins Posted October 7, 2009 Author Report Share Posted October 7, 2009 Thanks guys for the input. I'll look for clorox ... haven't seen it on the shelf though. Anyone familiar with a suitable brand in Australia? Since I ditched the "perfect balance" or PQ spa shield (buffering solutions), I have decided to go back to using calcium in the equation to manage my water balance (it didn't go well with this product due to one of the agents in it). Will hopefully be able to pick some up today. Checking this morning I can see a residue on the surface of the spa so I am fairly convinced it's the white king. I did check for other ingredients and nothing is listed (neither here nor there I guess). I'll clean my filters and try to pick up as much of the residue as possible and go from there. There is a homebrand bleach I might try too... could always just test it by shaking a diluted solution or aerating it... Quote Link to comment Share on other sites More sharing options...
mgrobins Posted October 8, 2009 Author Report Share Posted October 8, 2009 Bleach tested with a coffee plunger (to aerate)... White king => turns to foam Cheap arse Home brand => no suds at all... Was definitely the white king. Won't be recommending this to anyone! As for getting the residual detergent out of my spa.... any suggestions? I used a towel to drag over the surface and try to catch much of it and also one of my filter cartridges (gave them a clean). Also dropped in a small amount of the anti-foam as I thought it would counteract the bleach additive. I dislike adding anything not necessary for sanitation or balancing the water though. I reckon it just adds to the TDS and shortens the overall water lifespan between changes. Had my water tested. CYA is at 43 (a bit high I gather from recommendations) Other than dumping a few hundred litres I don't see a fix for this. Should this be considered a real drama? I tend to only use the chlorine or MPS to shock or just after bathing as I rely on the N2 and Ozone for the bulk of my sanitation. After advice I added calcium too. Using the pool calculator I don't know if I will be able to balance my water completely as my TA tends to be fairly low (50-60) when pH is kept at 7.8 or lower. Quote Link to comment Share on other sites More sharing options...
mcw53 Posted October 8, 2009 Report Share Posted October 8, 2009 Using the pool calculator I don't know if I will be able to balance my water completely as my TA tends to be fairly low (50-60) when pH is kept at 7.8 or lower. If by balancing your water you mean achieving a CSI of 0.00, I wouldn't worry too much about it. Being on the negative side is only a problem with plaster pools/spas. Not a problem with acrylic or fiberglass. I have very similar numbers as you (7.6-7.8 pH, 50-80 ppm adjusted TA, 180 ppm CH, 30 ppm CYA, 50 ppm Borates) and typically have a -0.20 to -0.30 CSI. I think this is far better than a high CSI which could lead to scaling. Quote Link to comment Share on other sites More sharing options...
mgrobins Posted October 8, 2009 Author Report Share Posted October 8, 2009 I re-tested my water with the following results. temp 37 pH 7.8 (after aeration). TA 80-90 CYA 43 Borate (unknown... added the described volume for startup and maintenance doses on the "spa silk" bottle which is bromic acid. I suspect it's fairly close to 50 as the total that has gone in over time is about 500g) - other than buffering this doesn't interact much anyway does it?? Incidentally, why are maintenance doses of Boric acid indicated on the packaging?? Is it consumed in reaction with other ions once dissociated? I was planning on using MPS but now that I found an ok bleach and have balanced my water I think I'll stick with chlorine. In an effort to get rid of the detergent/residue I ended up sitting a large sponge over the filter intake. Actually worked well as the sponge seems to have taken in the residue from the water passing into the filtration system. Quote Link to comment Share on other sites More sharing options...
chem geek Posted October 8, 2009 Report Share Posted October 8, 2009 I think the Borate amounts I gave in my earlier post were for 350 gallons. 500 grams of Boric Acid in 2100 liters would give 42 ppm Borates, which is fine. As for the CYA of 43 ppm, that's fine -- don't worry about it (I assume your 43 is an estimate between 40 and 50 lines in the tube). I don't know why they talk about maintenance doses since the Borates do not break down or go away. They can be diluted, but normally it's only pools that get a lot of splash-out. With spas, you just have some carry-out, but not that much. Evaporation doesn't remove it. You may find that having the TA lower will help keep the pH more stable. At 80 ppm, it will probably tend to rise with the typical aeration in a spa. At 50-60 ppm, it will be more stable (the Borates will help as well, but the fundamental driving force to carbon dioxide outgassing and pH rise is a higher TA). Quote Link to comment Share on other sites More sharing options...
mgrobins Posted October 8, 2009 Author Report Share Posted October 8, 2009 Thanks Chem Geek. I'm going to monitor the pH, TA and chlorine levels for a few days and see how stable it is with regular use. The aeration and CO2 was a consideration in where I tried to leave my TA (given that pH can sit in a range as well). I'm looking for the most stable and low maintenance water . I suspect that overall the extra Calcium will make things better. Next time I fill I reckon I'll be able to do it wiht minimal chemical wastage and a lot cheaper. This forum has helped me a lot . Quote Link to comment Share on other sites More sharing options...
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