Water Guru Sense 2

Hey guys, any updates regarding the s2? I'm on the fence between the iopool, sense 2, and the sutro. Really like most of what I've seen on the sense 2. Not a huge fan of the monthly expense of the sutro.
 
I have now been using waterguru sense 2 for 6 months. It's not perfect, but I am satisfied with it and would recommend it to others. Here are my thoughts on the product.

If there was an option of only using the C2 cartridges that only checks the pH and chlorine level daily, I would opt for that. I have found the pH to be accurate and within 0.1 of the pH measured with my taylor test kit. The chlorine is also accurate and within 0.5ppm of my taylor test kit.

The C5 cartridges record cyanuric acid, total alkalinity, and calcium hardness daily in addition to the daily chlorine and pH readings. On one hand, I don't need daily recordings of my cyanuric acid, total alkalinity, and calcium hardness levels. Secondly I have observed the total alkalinity and calcium hardness readings to be inaccurate. The cyanuric acid levels are accurate and within less than 10ppm of my taylor test kit levels. The calcium hardness levels are generally recorded 100-200ppm lower than than my taylor test kit levels. Moreover, the waterguru sense 2 calcium hardness levels fluctuate daily where the levels recorded by my taylor test kit are very consistent. The total alkalinity levels recorded by the waterguru sense 2 do not fluctuate like the calcium hardness recordings do, but they are still not accurate. The waterguru sense 2 generally records my total alkalinity levels in the mid 40s where my taylor test kit records it between 70-80.

All that being said, I would purchase the waterguru sense 2 again knowing what I know now. It frees me up from recording my chlorine and pH daily with my taylor test kit. I now only check it once a week with my taylor test kit. Another benefit of the waterguru, is that I can make adjustments to my chlorine generator remotely when I'm away from home if my waterguru reports a significant change in my chlorine levels.
My Ph is typically and consistently 2ppm too high. For example today, WG read 6.8 and FAS DPD was 4.8. Ph is close enough as I struggle with the color matching of the drop testing anyway.
 
Hey guys, any updates regarding the s2? I'm on the fence between the iopool, sense 2, and the sutro. Really like most of what I've seen on the sense 2. Not a huge fan of the monthly expense of the sutro.
I actually have both as I was given a Sutro and I have been trying it out for a few months to figure out which one to get rid of. In a nutshell, Sutro is too high on TA by quite a bit. Today Sutro said 101-120 and my Taylor 2006 with magnetic stirrer was 60, but that is not a big deal. I test it with Taylor 2 x week anyway. Sutro Ph matched WG and my liquid phenyl red drops so all good there. Sutro FC was 5 this morning and my FAS DPD gave me 4.8 and WG said 6.8. WG tends to read FC 2ppm too high but I like that it gives me the higher numbers, where Sutro stops at 5 and just states 5+ which is somewhat a limitation. I use liquid chlorine and target the high end of my Pool Math calculator at 8.

We are at this house typically on weekends only and maybe mid week for a day, so the remote testing is useful. However, I do know from experience how much liquid chlorine to add for a several day absence; I essentially shock it and let it drop back down in the Gulf Coast heat when we leave for a few days. For an extended absence, I can let a pool guy know to stop by and he will add what I ask him to, so the remote data comes in handy in that regard. Typically I will ask him to add two quarts of liquid chlorine and two cups of muriatic acid in the summer. The chlorine raises the Ph in the 7200 gallon pool in a pool that tends to have increasing Ph anyway.

The Water Guru app is much better and you can send in water samples and think they do a better job than Leslie's in that regard. Sutro app needs some TLC and updating. If I had to pick one, probably Water Guru. It is simpler. Both to me are just guides that cannot replace Taylor testing. I want to add a SWG to simplify this for me, but paying for my daughter's wedding took precedence :).

edit: I forgot to add three Sutro gives you 3 x readings/day at 8 hr increments which can be useful while WG I schedule for early morning one test a day. That said, one can request additional WG measurements if you need one via wifi or bluetooth.
 
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The Water Guru app is much better and you can send in water samples and think they do a better job than Leslie's in that regard.
Well the FC is no longer valid and IMO the PH had to change from all the jostles and vibrations in transit. The pool store is bad enough rattling in the cup holder the whole way. All the way back to WG HQ ? It's likely even more off.

The other parameters don't change much to need constant monitoring.
 
Well the FC is no longer valid and IMO the PH had to change from all the jostles and vibrations in transit. The pool store is bad enough rattling in the cup holder the whole way. All the way back to WG HQ ? It's likely even more off.

The other parameters don't change much to need constant monitoring.
I actually find their calcium hardness and phosphate (don't really care) are in line with my occasional Taylor testing of those parameters. CYA is typically close too. I have some sample tubes and I am trying to use them up. I agree, the mail lag and overall time delay makes things questionable and the analysis is more of an ok that is interesting thing. They do not measure FC and Ph as that would be old news.
 
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Well the FC is no longer valid and IMO the PH had to change from all the jostles and vibrations in transit. The pool store is bad enough rattling in the cup holder the whole way. All the way back to WG HQ ? It's likely even more off.

The other parameters don't change much to need constant monitoring.
It tends to match the test I did when I took the sample. But I don’t leave air in the tube.
 
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I always thought 7.4-7.6 was ideal. My ph goes up quickly, since I have swg, so I always get it down to 7.4 and once it gets to around 7.6 I adjust again. Are you saying this isn’t right?

Your pH goes up quickly mainly because you are trying to maintain it too low.

Only in a pool without CYA you need pH in the lower 7-half for chlorine efficiency reasons. In this case the HOCl concentration (which is the main sanitizing and oxidizing chlorine species) decreases by 50% from pH 7.5 to 8.0, turning into OCl-.

This changes with CYA, where the chlorinated cyanurates build a chlorine reservoir. This not only allows (even demands) higher FC levels, with more than 95% of what shows up as "FC" in the test bring chlorinated cyanurates and less than 5% being HOCl/OCl-. With rising pH, more chlorine gets released from the reservoir, compensating most of the HOCl that is lost by turning into OCl-. In total, HOCl now decreases from pH 7.5 to 8.0 by only about 15%, which can be neglected (and is considered in TFP's recommended levels).

This means that with CYA, pH is no longer critical for chlorine efficiency, which is why we recommend to maintain pH more on the 7.8 to 8.0 region, where dissolved CO2 gets closer to its equilibrium with atmospheric CO2, which means less CO2 outgassing and hence more stable pH.

Try letting pH drift up to 8 and then only take it down to 7.8. You will find that you have to add acid less frequently, TA will ideally find an equilibrium where your acid additions just compensate for TA increase by adding fill water, and you may never have to add baking soda ever again.

You don't want pH too much above 8, as metal staining becomes more of a problem (should there be dissolved metals in the water for whatever reason like having used algaecide or having low pH wrecked a heater, or from well water). And if you have high CH, then you should check your CSI and if that's too high you may have to decrease TA a bit to allow for higher pH without risk of scaling. But usually more of a problem for those in hot and dry desert climates.

And it's still important to lower pH to the lower 7s before a SLAM to avoid high pH during a SLAM.
 

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Your pH goes up quickly mainly because you are trying to maintain it too low.

Only in a pool without CYA you need pH in the lower 7-half for chlorine efficiency reasons. In this case the HOCl concentration (which is the main sanitizing and oxidizing chlorine species) decreases by 50% from pH 7.5 to 8.0, turning into OCl-.

This changes with CYA, where the chlorinated cyanurates build a chlorine reservoir. This not only allows (even demands) higher FC levels, with more than 95% of what shows up as "FC" in the test bring chlorinated cyanurates and less than 5% being HOCl/OCl-. With rising pH, more chlorine gets released from the reservoir, compensating most of the HOCl that is lost by turning into OCl-. In total, HOCl now decreases from pH 7.5 to 8.0 by only about 15%, which can be neglected (and is considered in TFP's recommended levels).

This means that with CYA, pH is no longer critical for chlorine efficiency, which is why we recommend to maintain pH more on the 7.8 to 8.0 region, where dissolved CO2 gets closer to its equilibrium with atmospheric CO2, which means less CO2 outgassing and hence more stable pH.

Try letting pH drift up to 8 and then only take it down to 7.8. You will find that you have to add acid less frequently, TA will ideally find an equilibrium where your acid additions just compensate for TA increase by adding fill water, and you may never have to add baking soda ever again.

You don't want pH too much above 8, as metal staining becomes more of a problem (should there be dissolved metals in the water for whatever reason like having used algaecide or having low pH wrecked a heater, or from well water). And if you have high CH, then you should check your CSI and if that's too high you may have to decrease TA a bit to allow for higher pH without risk of scaling. But usually more of a problem for those in hot and dry desert climates.

And it's still important to lower pH to the lower 7s before a SLAM to avoid high pH during a SLAM.
Wow… you kinda blew my mind with this. I will definitely try, what you’re recommending. Thanks for the detailed information.
 
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I actually have both as I was given a Sutro and I have been trying it out for a few months to figure out which one to get rid of. In a nutshell, Sutro is too high on TA by quite a bit. Today Sutro said 101-120 and my Taylor 2006 with magnetic stirrer was 60, but that is not a big deal. I test it with Taylor 2 x week anyway. Sutro Ph matched WG and my liquid phenyl red drops so all good there. Sutro FC was 5 this morning and my FAS DPD gave me 4.8 and WG said 6.8. WG tends to read FC 2ppm too high but I like that it gives me the higher numbers, where Sutro stops at 5 and just states 5+ which is somewhat a limitation. I use liquid chlorine and target the high end of my Pool Math calculator at 8.

We are at this house typically on weekends only and maybe mid week for a day, so the remote testing is useful. However, I do know from experience how much liquid chlorine to add for a several day absence; I essentially shock it and let it drop back down in the Gulf Coast heat when we leave for a few days. For an extended absence, I can let a pool guy know to stop by and he will add what I ask him to, so the remote data comes in handy in that regard. Typically I will ask him to add two quarts of liquid chlorine and two cups of muriatic acid in the summer. The chlorine raises the Ph in the 7200 gallon pool in a pool that tends to have increasing Ph anyway.

The Water Guru app is much better and you can send in water samples and think they do a better job than Leslie's in that regard. Sutro app needs some TLC and updating. If I had to pick one, probably Water Guru. It is simpler. Both to me are just guides that cannot replace Taylor testing. I want to add a SWG to simplify this for me, but paying for my daughter's wedding took precedence :).

edit: I forgot to add three Sutro gives you 3 x readings/day at 8 hr increments which can be useful while WG I schedule for early morning one test a day. That said, one can request additional WG measurements if you need one via wifi or bluetooth.
So I got a Sutro and for the last 48hrs with it my initial thought is to send it back and try the waterguru. This app literally takes forever to load pages, the setup process was like an hour of me forcing the app closed to restart it just to get to the next page of the setup. My readings are not even close to my Taylor kit, I went to the local pool store today and had my water tested with their lamotte spinner and got the same results as my Taylor kit. Right now the Sutro is reading my alkalinity at 31-50 and Taylor says 100. It's reading FC at 5+ when Taylor is at 2. PH is reading 7.3 and Taylor is 7.4. Yesterday my Taylor test read 7.9 PH and the Sutro read 7.4, I put half a gallon of MA in this morning and the Sutro read it twice today at 7.3.

Edit: 10 minutes after writing this I got an email from Sutro that there is currently a delay with monthly cartridges due to "widespread shipping issues affecting carriers globally, leading to delays"
 
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So I got a Sutro and for the last 48hrs with it my initial thought is to send it back and try the waterguru. This app literally takes forever to load pages, the setup process was like an hour of me forcing the app closed to restart it just to get to the next page of the setup. My readings are not even close to my Taylor kit, I went to the local pool store today and had my water tested with their lamotte spinner and got the same results as my Taylor kit. Right now the Sutro is reading my alkalinity at 31-50 and Taylor says 100. It's reading FC at 5+ when Taylor is at 2. PH is reading 7.3 and Taylor is 7.4. Yesterday my Taylor test read 7.9 PH and the Sutro read 7.4, I put half a gallon of MA in this morning and the Sutro read it twice today at 7.3.

Edit: 10 minutes after writing this I got an email from Sutro that there is currently a delay with monthly cartridges due to "widespread shipping issues affecting carriers globally, leading to delays"
My Sutro FC and Ph readings are closer than that vs Taylor, but Sutro alkalinity is always too high vs Taylor whereas yours is going the other direction. I consider it a guide and not a substitute for Taylor testing, but we are only here 1/3rd of the time so I do like getting some readings. I have enough run time to be able to manually adjust in my head. Initial set up took some effort, but going forward it has been relatively easy to swap cartridges. The shipping delay makes me think the cartridges are made overseas somewhere and/or more to the story than they are saying.
 
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My Sutro FC and Ph readings are closer than that vs Taylor, but Sutro alkalinity is always too high vs Taylor whereas yours is going the other direction. I consider it a guide and not a substitute for Taylor testing, but we are only here 1/3rd of the time so I do like getting some readings. I have enough run time to be able to manually adjust in my head. Initial set up took some effort, but going forward it has been relatively easy to swap cartridges. The shipping delay makes me think the cartridges are made overseas somewhere and/or more to the story than they are saying.
I got the Sense 2 a couple days ago and have been impressed, it read within a margin or error across the board with the new 5 way test cartridge. I like the app a little bit more also, but that is subjective, as long as the product does it's job at the end of the day that's all that matters. I did notice the 5 way test cartridge is out of stock frequently but only time will tell how that plays out. I do like being able to just buy the cartridges vs a subscription, the Sutro only lets you test on demand if you have the premium tier subscription, while the Sense 2 lets you test whenever as long as your cartridge isn't empty.
 
I've had the Sense 2 for about 2 months now and I like it a lot. As this is my first time taking care of the pool myself, it's nice to see how the trends move and I can head off any problems as they come up. I don't want to test every day and this is a way for me to see how everything reacts as a whole. The color testing is difficult for me to differentiate so discrete numbers are good to reference. After a while I may get the whole thing down, but this is great for newbies and data needs like myself.
I changed their recommended ranges to the TFP ranges in the web interface and I am just tweaking what pH and chlorine levels I feel comfortable with and how often I need to add chemicals now. I don't want to have to stress about getting the pool just right the days before a pool party and the Sense let's me see a nice snapshot. I wish the app let me change the ranges, but I have the web page bookmarked on my phone so I just jump in the few times I had to change it.
Note it is not a continuous test. It runs once a day unless you manually run it. I figured this when I bought it, but it's not very clear on the website.

Does anyone know if you can stop using a cartridge mid month and start it up again later? I've been meaning email them to ask, but thought I would ask.
 
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I had the sense 2 for about a month. FC & PH were close but not in line with the TF Pro Salt. I was most interested in the CYA, TA & CH since it is a brand new pool but the numbers fluctuated widely.

This was the response from customer service when I asked the question:
"Please know that while our FC and pH pads use custom WaterGuru proprietary chemistry, the TA and CH pads we are using are currently unmodified, direct from the Test Strip manufacturers, while the CYA pad is a hybrid.

Due to this, the three parameters may not align with the other test results. Rest assured, we are continuing to improve the algorithms for the CYA, TA, and CH pads as well as making continued improvements to the pads and pad manufacturing process. "

Bottom line it has great potential and if you only need FC & PH have at it. Customer service is very responsive to issues. If you are looking for CYA, TA & CH you may want to hold off till they are further down the road.
 
I had the sense 2 for about a month. FC & PH were close but not in line with the TF Pro Salt. I was most interested in the CYA, TA & CH since it is a brand new pool but the numbers fluctuated widely.

This was the response from customer service when I asked the question:
"Please know that while our FC and pH pads use custom WaterGuru proprietary chemistry, the TA and CH pads we are using are currently unmodified, direct from the Test Strip manufacturers, while the CYA pad is a hybrid.

Due to this, the three parameters may not align with the other test results. Rest assured, we are continuing to improve the algorithms for the CYA, TA, and CH pads as well as making continued improvements to the pads and pad manufacturing process. "

Bottom line it has great potential and if you only need FC & PH have at it. Customer service is very responsive to issues. If you are looking for CYA, TA & CH you may want to hold off till they are further down the road.
I had not used a C5 cassette for awhile and I have observed that TA, CH and CYA are rather close to my Taylor K2006 results over the last two weeks. I was pleasantly surprised as in the past those parameters were way off and quite erratic. Maybe they are getting them dialed in. FC is still a tad high, but that is a mental adjustment and Ph is good; at least vs my ability to match various shades of red.
 
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Cut out the tab feeder and add a vertical loop. The flow switch needs 'up flow' so gravity can't close it when the spring fails. (When...... not if).

Some units have the flow switch in the cell, others have a seperate switch. If all in one, the cell goes on the up pipe. If seperate like the Circupools, the flow switch goes on the up pipe and the cell goes on the down pipe.

View attachment 553635
I just sent this to my pool company to discuss, but an install looks rather simple so that I could probably do it myself. I do not want to void any of my 3 year warranties, so I figure I need to work with them first. The harsh Gulf Coast environment has required several warranty repairs even after 18 months. I will let you know what I find and I appreciate this. Fred
 
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Thought I would chime in with some additional thoughts. I inherited a Sense 1 when I bought the house and it gave me nothing but problems (least of which was the battery housing that opened up dumping them into the skimmer). I ended up buying another one when it finally gave out, only to have that break down so about 3 months ago they sent me a new Sense 2 for free.

For starters, I think the customer service is outstanding. They are super responsive to emails to their support. They answer calls quickly and resolve issues on the spot. Case in point, when my newish Sense 1 broke down, I called in and they were able to trouble shoot it remotely and within a few minutes with the rep interfacing with their tech guru, she was able to tell me that the unit was defective and they would send me out a brand new Sense 2.

They have also had problems with supply of cassettes, so most recently they began selling single Sense 2 C2 separately from C5 (was usually bundled in 3 packs of 1 C5 and 2 C2 or 3 packs of C5). They may be going back to bundling again once they fix the supply issue but I'm hoping they will still sell 3 packs of just C2 cassettes which last 2 months instead of C5 which only last a month (I had emailed them about the fact that C5 is really only necessary for start up or major adjustments and so from an environmental impact standpoint, it is a waste-- they responded they would look into it as others have complained about this so we'll see what happens).

I agree with most poster's assessment that the unit is most useful for FC and PH as an additional tool for my weekly-ish tests using TFT kit. For me the FC is lower than my TFT DPD test, but I think it is internally consistent and helps to alert me to when I should do a weekly test. Also, the pool is in a second home so it's imperative that I have remote testing to be able to keep "eyes" on the pool. I also find the flow and temperature readings helpful to alert me if there is a pump issue, water level issue, heater issue, etc. I also think the other readings internally consistent (they go up and down as expected with additional of chemicals or adjustments, so while not totally consistent with TFT tests they still are helpful as gauges for when I need to pay closer attention to the pool chemistry. Also CYA readings in the TFT kit, as the kit says itself is pretty subjective given that you are staring hard at that black dot at the bottom (am I seeing it or just a ghost image from my retina?), so in some ways I find the Waterguru CYA consistent, but perhaps 10 pts above what I "eyeball" with TFT.

I think they need to allow adjustments to their testing frequency (which may run counter to their business model of selling cassettes, but who knows maybe they'll change that). In the winter in the Napa area (doesn't freeze), I end up installing a used "dummy cassette" and still keep the unit in the skimmer to keep tabs on flow and temp, since I don't really need to do daily testing, or as per their customer service, you can just remove the unit and store for winter.

Overall, I give props to Waterguru as a company and think it's useful for those pool owners who need to have an additional tools to keep eyes on their pool. If you can afford it, I think its worth it.
 
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