Would you invest a grand for a KH Guardian?

[Willz]

So you are too cheap to buy it and anyone who does want to buy it has impulse control issues? Nice paint brush. You must be frustrated because no one responded to your last post 6 hours ago.

"Cheap" isn't the word you were looking for friend, it is "smart". Take care

 

[iiluisii]

"Cheap" isn't the word you were looking for friend, it is "smart". Take care

Great reply [emoji95][emoji1420][emoji95]

 

[Jonty]

yes close it, sad how the community is acting

 

[rockworm]

yes close it, sad how the community is acting

I agree. I was acidic in my most recent response. @Willz, I was wrong and apologize for it.

I think system size has a significant impact on a persons perception of value. I started with a 90g in 2005/6 (can't remember the exact date). Over the years, I have upgraded to where I have reached my dream tank, a 400g SPS tank with a secondary 75g LPS.

I went from a 90 to a 180(plus a couple small tanks) to a 220g before the 400g. I would not even consider a $1000+ alk monitor/doser for my 220g. It had a mix of SPS and LPS and the price of the KHG would not make sense.

I have probably spent close to $40k over the years for equipment and house modifications to get to my current end state. Now that I plan to use the 400g for SPS, the incremental cost for an alk monitor/dosing system seems reasonable for me. Yes, I can still use my Hanna Alk checker on a regular basis, but I see value in the alk monitor that is discussed in this thread.

Value is a very personal thing and the personal value for any given item should be equal or greater than the price. For example, I love football and will pay for the NFL network because I want access to all the games on Sunday. However, I am not a basketball fan and have no interest in buying the NBA channel. I really like the idea of an alk monitor that can dose a little baking soda where it is needed. It just allows me to be a little lazier.

There have been many good suggestions and opinions expressed in this thread and I am glad that it has stayed open for comments.

 

[SCSI]

I see many posts here where I suspect that the terms "accuracy" and "precision" are being confused / conflated / misused.

"resolution" is another term I would add to the confusion list. In case with KHG, it is stated in many places that specified accuracy (0.1 or 0.33) is the same as resolution (also 0.1/0.33). This is very unusual to see and doesn't add too much credibility to the stated accuracy value(s). Typically you would expect to see "resolution" to be around 10x better than stated accuracy.

On a side note, accuracy of 5% of reading is very acceptable for any analytical instrument of this [consumer] grade. In this case 5% is approximately 0.4 dKH. In order to get to 1% of reading or 0.04 dKH, I would expect to see some substantially different hardware at much higher price. Note that by saying this I'm not defending KHG's 0.33/0.1 values. Just saying that majority of analytical instruments for wet chemistry analysis getting away just fine with 5% accuracy or sometimes with 5% of Full Scale values. The ones that perform with 1% margins costs tens of thousands and definitely don't use the cheapest pumps a man can buy.

I guess what I'm trying to say is that I would want to see some test data behind the 0.1 dKH accuracy statement.

 

[Frop]

My entire spending history is under $1,600 (including the new upcoming tank build). So.. not worth it unless I have way more in it. I wouldn't buy a computer now unless I found a really good deal on a used one.

 

[JimWelsh]

"resolution" is another term I would add to the confusion list. In case with KHG, it is stated in many places that specified accuracy (0.1 or 0.33) is the same as resolution (also 0.1/0.33). This is very unusual to see and doesn't add too much credibility to the stated accuracy value(s). Typically you would expect to see "resolution" to be around 10x better than stated accuracy.

On a side note, accuracy of 5% of reading is very acceptable for any analytical instrument of this [consumer] grade. In this case 5% is approximately 0.4 dKH. In order to get to 1% of reading or 0.04 dKH, I would expect to see some substantially different hardware at much higher price. Note that by saying this I'm not defending KHG's 0.33/0.1 values. Just saying that majority of analytical instruments for wet chemistry analysis getting away just fine with 5% accuracy or sometimes with 5% of Full Scale values. The ones that perform with 1% margins costs tens of thousands and definitely don't use the cheapest pumps a man can buy.

I guess what I'm trying to say is that I would want to see some test data behind the 0.1 dKH accuracy statement.

Regarding "resolution", for my MACNA prototypes, I considered it to be 0.001 meq/L, or around 0.003 dKH, but in practical terms for my implementation, you could say it was the least significant digit on the display, or 0.01 dKH.

For the prototypes I brought to MACNA, I was claiming +/- 0.05 precision (meaning a coverage factor of k=2, or twice the Standard Deviation), which was a conservative claim, considering that the underlying data supported a claim of +/- 0.03 dKH. Here is an image (below) I posted on Facebook right before heading off to MACNA, of four hours of running a 7.0 dKH standard every 10 minutes, for a total of 24 tests. The Mean of this run is 6.99, and the Standard Deviation is 0.015 dKH, for a RSD of 0.2%, or an uncertainty (k=2) of 0.03 dKH. So, I have been able to achieve much better than 1% performance for much less than tens of thousands of dollars, and both have the data to back that up, and have also publicly posted it already in the past.

 

[SCSI]

@JimWelsh - that's a very respectable performance numbers. On the border of believable provided I haven't seen the guts of the blue box. Hope you didn't think I was questioning your numbers in my previous post though I can do that with pleasure For example, what range of ambient temperatures did you test it in? You know I'm pulling your leg with this one, but it's going to be an important parameter all respectable analyzers are specified for. For hobby use we can shrink it down to, say 20C-50C or whatever is the typical temp range around the sump area. Some people put their chillers in there and they cycle ambient temps quite a bit.

Seriously though, it would be very interesting to see similar (or half as detailed) test data for the KHG device. Ideally describing test conditions and environmental data.

Thanks,
Kirill

 

[JimWelsh]

@JimWelsh - that's a very respectable performance numbers. On the border of believable provided I haven't seen the guts of the blue box. Hope you didn't think I was questioning your numbers in my previous post though I can do that with pleasure For example, what range of ambient temperatures did you test it in? You know I'm pulling your leg with this one, but it's going to be an important parameter all respectable analyzers are specified for. For hobby use we can shrink it down to, say 20C-50C or whatever is the typical temp range around the sump area. Some people put their chillers in there and they cycle ambient temps quite a bit.

Seriously though, it would be very interesting to see similar (or half as detailed) test data for the KHG device. Ideally describing test conditions and environmental data.

Thanks,
Kirill

Just a bit more data to support my claims. As soon as I returned home from MACNA, I posted on Facebook an image (below) of the graph of the two prototypes I took to MACNA running simultaneously on the same tank, this time every 10 minutes over a period of more than 24 hours. Please understand that this data is somewhat affected by "noise" from the BNC cable interface to the Apex, so the underlying actual data from the instrument is even tighter than this, but for the purposes of this conversation, let's take this graph at face value. It still strongly supports the precision and accuracy I cited earlier. I hope it is "believable" enough!

I, too, would like to see supporting data for the KHG claims.

 

[SCSI]

I hope it is "believable" enough!

Nope, it's even worse now. Definitely too good to be true

I think I followed the discussion on daily fluctuations of alkalinity you discovered. I wonder by how much measurements were influenced by ambient air temperature. It would be interesting to see if there is any correlation. Do you have an internal temp sensor by any chance?

 

[JimWelsh]

Nope, it's even worse now. Definitely too good to be true

Glad you liked it!

 

[Lninwa]

It looks like it is also a foster. Is that so?

 

[Lninwa]

If Neptune is open to working with us, we are more than happy to our best to make it happen.

Neptune is also working on an alk monitor.

 

[eltonw]

KHG is a full control system it is not a simple test unit. If you only need monitor function it is really a simple requests to KHG. We can provide KHG Monitor only device within one month.
KHG has 3 major dominant positions.
1.Stable
2.Auto control
3.Huge history test data base.

KHG has been test 4 years test history here we only request few users provide smart phone screenshot to show on this thread.

MORE IMPORTANT THING IS ALL OF THEM ARE USING ON THE TANKS NOW BUT NOT A PROTOTYPE OR THEORY ITEM.

 

[eltonw]

Here is another use he use on his tank with high KH value request. But in his case he makes the soda water MQL at ZERO supply and still use his current dosing pump do the supply job.

 

[eltonw]

Let me show you one tank with high end SPS and fish. This tank use KHG over years and KHG keeps not only him happy but also fish and SPS growth.

 

[eltonw]

When I asked one of our user to send me his data but he was traveling and he still can make a screenshot for my reference thru Telekom.de service to check his KH value.

 

[eltonw]

Even some shops and coral frames in Taiwan also use KHG to keep their SPS healthy. What I can say...SABLE AND TRUSTED

!!!

 

[eltonw]

Even some shops and coral frames in Taiwan also use KHG to keep their SPS healthy. What I can say...SABLE AND TRUSTED

!!!

 

[iiluisii]

Let me show you one tank with high end SPS and fish. This tank use KHG over years and KHG keeps not only him happy but also fish and SPS growth.

If this is the tank Im thinking of this tank has change more configurations in the past 5 years that I ever seen. I mean even corals.