Hello, I have looked at the recommended test kits and wonder if the TF-50 would be the best as long as I have separate ph test strips?
Best test kit for small (215 gal.) spa?
- Thread starter send2lorrie
- Start date
- May 23, 2015
- 25,681
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
I would get the Taylor K-2105 (Welcome to Taylor Technologies) if you intend to run your spa with chlorine and CYA. It ain't cheap but I think it's worth it.
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- May 23, 2015
- 25,681
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If you happen to find the Taylor K-2105-C, that is the "commercial" version which uses 2oz reagent bottle sizes as opposed 0.75oz bottles in the K-2105-A kit.
OK, I don't see the commercial version on Amazon, and you are saying there is a K-2105-A kit? Is that different than the K-2105, because I don't see that either. We just did a fresh fill after realizing we had way too much CYA so hoping to keep it good for a while, still learning, thanks!
- May 23, 2015
- 25,681
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If the part number just says "K-2105" than it is more than likely the K-2105-A which is the "residential" version. The commercial version ("-C") would be more expensive. The difference is just the reagent bottle sizes. The C version has larger bottles.
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If it helps at all, I found the "C" version here: Taylor Service Complete Test Kit - Low Range K-2105C
Do you think the K-2006 is better than the K-2105? I understand the difference with the C for commercial providing more in the bottles, thanks. I do see the K-2006C on amazon for $94 incl shipping.
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The major difference between the 2105C and the 2006C is how you test for free chlorine (FC) and combined chlorine (CC). The 2105 uses the DPD test and the 2006 uses the FAS-DPD test which is the goal standard of chlorine testing.
If the kits are the same price, get the 2006C with the FAS-DPD tester!
If the kits are the same price, get the 2006C with the FAS-DPD tester!
- May 23, 2015
- 25,681
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
For a hot tub/spa, the high end test kits are often overkill. There's no need to test CH in a spa because it's really not that important and, if you know you have low hardness water, you can just add a little CH increaser based solely on the packaging directions. For chlorine, you can use the DPD only test to give you a very decent read of the FC level, especially if you pair it with the high range comparator block (#9056 reads shades of pink from 1-10ppm). TA is important to know as is pH. CYA isn't necessary to directly measure because in the dichlor-then-bleach method you will add enough dichlor (in batches) to achieve 30ppm CYA and then switch over to bleach. Even if you keep your spa water for 4+ months, you shouldn't need to add any dichlor.
The Taylor K-2015 is a spa-based combo kit that measures pH, FC/TC and TA. That one should be all you need.
The Taylor K-2015 is a spa-based combo kit that measures pH, FC/TC and TA. That one should be all you need.
Just keep in mind that low CH can be culprit of foaming. If the water foams up with the jets running then raising CH to 120-150 can help to eliminate foaming.
I disagree with these statements.
DPD only test doesn't test for Combined Chlorine. I don't have any experience with the high range color block, but the one with my K1000 isn't very accurate at all compared with the powder-drop chlorine test.
I haven't found any need to know what my TA is either (no plaster/grout). Just PH.
CYA levels decline over time in my experience. Splash-out causes it to go down. Also, chlorine slowly eats away at it. I suspect that the higher temps in spas speeds this process relative to pools. I'd certainly recommend that folks lower their PH with dichlor after doing a SLAM, or as a monthly adjustment, especially if they are not testing for CYA.
That's my two cents.
- May 23, 2015
- 25,681
- Pool Size
- 16000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
There are several things wrong with these statements.
First off, the K-1000 has a chlorine test based on the OTO chemistry (shades of yellow). OTO measures total chlorine (TC = FC + CC) only and, as you state, is very inaccurate. This is why I do not use it. The kits that have been mentioned so far have a chlorine test that is based on the DPD (N,N-diethyl-p-phenylenediamine) which shows up as shades of pink. DPD is sensitive to free chlorine (FC) and gives very accurate results. I have compared FC measurements using both DPD-FAS titration and DPD-only color matching and they are dead-on equivalent. Also, one only needs to add the required amount of the R-0003 reagent to the DPD-only test, and you can measure both FC and TC (CC = TC - FC). IN fact, the DPD-only test can be titrated with the R-0871 reagent and you can get the same exact results as using the DPD-FAS test.
In short, the R-0001/R-0002 DPD-only test is completely accurate and repeatable and perfectly suited for a hot tub.
As for total alkalinity (TA) in this scenario (a hot tub), it has nothing to do with plaster. The primary action of TA and the reason why one should know what it is, is for pH stability. TA is a measure of the primary buffering capacity of the water and is important to know whether you're talking about a pool or hot tub. When TA is high (over 100ppm), outgassing of CO2 from a body of water (spa or pool) will cause the pH to rise very quickly. This will cause excess acid demand. If the TA gets too low (below 40ppm), the pH of the water can become unstable and begin to fluctuate wildly. So knowing TA is critical for a spa to keep the pH steady as well as protect the heater from water that could become too corrosive.
In the dichlor-then-bleach method of spa care, one adds dichlor in small batches until the CYA reaches 30-40ppm. Every 10ppm of FC added by dichlor adds 9ppm CYA. Even in a hot tub, the loss rate of CYA to oxidation by chlorine is only about 5ppm/month. So, in 4 months, one could expect to lose about 20ppm. If you start off with 40ppm CYA in the tub, then one would still have 20ppm CYA left. The purpose of CYA in a hot tub is to moderate the concentration of active chlorine (hypochlorous acid/hypochlorite ion) to make the water more comfortable to soak in and so it acts as a chlorine buffer. With 20ppm FC, there is still substantial buffering of the chlorine. As well, in a properly sanitized and maintained tub, there will be almost no algae growth possible. The biggest concern is bacterial biofilms and disease transmission. Bacteria and viruses are easily killed by chlorine even in water that has just 1ppm FC and 20ppm CYA.
This hasn't been my experience. Without getting into that, alls I'm saying, is, folks may want to test for it.
As for TA, if its too high, you'll know from testing the PH. Lowering the PH will lower the TA as well, and you'll know when your good from testing the PH, cause it will stop rising so fast. Chlorinating with bleach means that TA is always slowing rising, so in that case, it won't get too low.
The chlorine testing info is interesting. Thanks for clarifying that.
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