jakenz

Thanks Chem Geek, very informative as usual and exactly what i wanted to know. Yes i am using liquid chlorine, with great success, only issue i have it salt levels building up quite quickly as my background chlorine usage is around 5ppm, not sure why it is this high, could be due to an old cover.

Im not very knowledgeble on the subject, but with a quick internet search i came across this https://confluence.cornell.edu/display/AGUACLARA/Calcium+Carbonate+Settling+Observations It seems to support what i was told in the shop? Im in New Zealand, and the best i could find with an internet seach was budget premium bleach at 4%, but could not find it where it was claimed to be stocked. That link about the shelf life of liquid chlorine was very informative, thanks for that.

So i was down at the spa shop today, and got talking to the guy who runs the place rather than the guy who usually runs the tests for me and i explained the system i was running to him, dichlor then bleach, with borax. After initially telling me that only idiots use liquid chlorine because of the shelf life and weight, and i explained that with the use our spa gets, dichlor builds us the cya too quick, lithium is too expensive and cal-hypo increases hardness. He then told me what they do, add a quanitiy of cal-hypo to water, mix, half an hour later mix again, then leave for a week is a cool dark spot, the calcium settles to the bottom or on top, and you can take the green chlorine solution and leave the calcium behind, dilute this to the to the right strength, ie 6% and you are sorted. Now for me this sounds very attractive as the strongest bleach i could find that i could use for the spa was 3% and expensive, and liquid chlorine is $30 for 5l around here, unless i buy 20l at a time. Any thoughts on this method?

I had the water tested and the cya came back at 40, usually comes back between 35 and 60. I thought i might have been getting somewhere, there was a 4ppm residual this morning, however i opened the cover tonight and it smelled rank and the fc was down to 0 again, dumped in the rest of our dichlor, maybe 15g and will have another look tomorrow morning. I checked the strength of the chlorine, its around 9% judging by how much it raises the FC in the spa. Is our spa just a dud?

Im stuck again and not sure what to do, most of my numbers are ok now, apart from FC, the usage is crazy. The CD had been high so i have been shocking 20ppm for about a week now, this is taking additions of 200ml of 10% twice daily and i test twice daily and by the evening and again in the morning its down to 2ppm again, last night i shocked to 50ppm as was suggested on one post and its down to 10ppm already ~20 hours later. The filters are about a month old and get rinsed twice a week. The water in the spa is crystal clear, ive never seen spa water so clear. And yet our CD is through the roof, what do i do?

Hi, I am pretty new to this so cant offer to much advice on the matter. However i can tell you that when we moved our spa out to an older shed, we immediaty began getting electric shocks from the spa. We traced this back to a faulty ground and once this was fixed we stopped getting shocked. So my thoughts on the matter are, if you are not getting shocked, your spa is properly grounded. Although that is a not a very good test i admit. One thought i did have regarding your spa was the use of an automatic liquid chlorine feeder. This would allow you to get the benefits of the use of liquid chlorine, with the ability not have to worry about it when you go away.

I have been using the local pool and spa shops to get testing done, have noticed a few wild readings that i ignore, but mostly seem to be ok. I used alot of ph down to counter the rise from adding borax, but even after i got it back down it continued to rise, ta is around 40 now, and judging by the test strips, not very reliable i know, but the pH seems to not be getting too high. I think the CH is around 200 now, and have changed to liquid chlorine, cant get good bleach around here.

Another pool test today, TA 25ppm, PH 8. Kinda lost as to what to do now

What would you recommend as the CH level to aim for?

Yeah i think ill aim for 5ppm, spa should currently have around 30ppm cya, water test from the local spa shop says 60, but im doubting the accuracy of that, Going by the pool calculator, with my current TA of 50, i need a really high CH to compensate for that, in the region on 400ppm, i have taken the spa to 160ppm with calcium chloride, do i need to take this higher, or it it ok to just use calcium hypo as our source of FC and not worry about it?

No our spa does not have an ozonator, we thought about getting one, but do not have the money for it at this stage. Thanks for the advise, i think that finding the right dosage after bathing will be the next thing i have to get sorted. We have found no issues with using the spa even with high FC levels of around 10ppm, so maybe before a party just get the FC fairly high then redose halfway though, with a couple minutes out of the sps to let it mix. I added borates to the spa yesterday, so hopefully that will help with keeping the ph steady, have been finding that the ph rise has been difficult to keep on top of due to 2 of the jets having air constantly coming through them regardless of the setting.

Thanks chem geek, As for the amount of people in the spa, we got in at about 5pm with 7 of us in it and everyone was out of the spa by 12, the amount of people dwindled a bit towards the end of the night, but there were probably about 12-15 different people using it in total, but this has been our biggest night so far and with the amount of cya in at that stage required the spa to be drained as it was still cloudy 3 days later with a FC ppm of over 10 constantly. Also the spa has been used the past 2 nights with the new fill, 1st night with 4 people for 2 hours, and the 2nd 2 for an hour and a half, after the first night i added 56ppm of FC to find that by the time we came to use the spa tonight it was still over 10ppm, and after an hour still over 10ppm, (according to the test strips we have) so i feel maybe 56ppm was too much? The spa is mostly used for watching movies, so is set for 38c and gets turned off during and dips to about 34-35 by the end, so in that regard maybe the bather load is lightened. I like the idea of adding 20ppm at a time after high use, do i keep doing this until i have added the required amount of ppm for the load, or until the FC stabilises? I did a search for the sp 300 and found nothing, but it looks like there is a stockist in nz for palintest products so i will get in touch with them and see if they can get one in. My apologies if my message is a little hard to read, St Patricks day today.. Thanks again

Hi Everyone, Great forum, i have learnt a lot over the last week reading and rereading how to maintain a spa. I am a university student flatting with another 3 guys, just recently we decided to get a spa, and have purchased a 1050l (275 gallon) tub. After a few, well more than a few false starts, especially with using dichlor and the cya very quickly getting out of control i have decided to start using the dichlor then bleach method. The first issue im having is getting a decent water testing kit, the Taylor K2006 seems to be what is recommended, however it is not available in New Zealand, does anyone know of an alternative, or a way for me to get a taylor over here. The biggest issue im facing is bather load, being at university having a spa has attracted many other students over for parties, in which alot of drink is consumed and probably spilled in the spa. One night we had an average of 6 people in the spa for about 6 hours, all getting in and out constantly. I worked this out using the 7ppm per person per hour method, i understand that this is for a 350 gallon tub so in reality its probably more, anyhow this comes to a whopping 252ppm of FC needed after the party! To be honest i dont know what to do here, this seems like a far to greater amount of chlorine to be adding at once, i understand that some of this will be needed to be added during the night to maintain some level of FC, but it will still be a huge dose at the end of the night. If someone could advise me on how to cope with ths situation it would be very much appreciated. Thanks in advance