KH Guardian: Automatic Alkalinity Controller- My Experiences

[Rick.45cal]

It is 7 for est.

Actually it's -5

The system time of your LAN will display on the KHG screen, but when it records to your SD card it will use the timezone conversion. Which is why the last entry in his photo is for Feb 18 at 6:45am.

I know the CoralVue video says to put a 7 in there for EST, but that is actually 7 hours ahead of the International dateline, and we are 5 hours behind the international dateline.

(It took me awhile to figure out why it wasn't recording the time in the log as what was provided by the LAN and confirmed by the time on the KHG machine itself).

Sounds like you should check and adjust your setting as well.

Just FYI, once you change it, it won't alter the recorded results, but your new tests will record with the proper time and date then!

 

[Rick.45cal]

Fixed, Thanks!! at lease there will be one thing accurate

 

[Jonty]

I remounted my unit today and have been able to get the run from the SW in pickup to be less than 12 " so I should be getting a totally clean sample with no residual SW sitting in the line from the last test. I am also now dumping the effluent into a floor drain rather than the tank.
My tanks are all on one system so I have it mounted next to my fishroom observation tank next by my testing desk.
Untitled by watsonj0, on Flickr

 

[Rick.45cal]

Looks good Jonty! My SW in line is very short too, probably just slightly longer than 12"

 

[CoralFragZ]

I remounted my unit today and have been able to get the run from the SW in pickup to be less than 12 " so I should be getting a totally clean sample with no residual SW sitting in the line from the last test. I am also now dumping the effluent into a floor drain rather than the tank.
My tanks are all on one system so I have it mounted next to my fishroom observation tank next by my testing desk.
Untitled by watsonj0, on Flickr

Looks good. You can get acrylic action figure cases on ebay for pretty cheap. I prob would help keep it clean. I am moving mine to my LPS tank as I am not sure it can be trusted and seems like tech support has communicated it is working correctly even though it swings .4 and has missing numbers. I shall still wait for an enterprise alk checker for the farm! It will be useful on the LPS tank as alk swings are not a major factor for LPS and I usually check alk there once every few weeks!

 

[nelson.jdautobody]

Following

 

[Rick.45cal]

@Jonty @Rick.45cal
Dosen't keeping the SW line under 3' as suggested make sure that it is fresh water being tested, because what is in hose is used for the rinse before testing?

Yes, the instructions say under 100 cm. I'm also surmising that you want to limit the diameter of the tube running to the unit as well, since increasing the internal diameter of the tube to something wider is going to increase the volume that is contained within it. My run is exceptionally short because of the location my unit is in relation to my sump.

So using your chart you created showing the mathematical errors induced by the conversion factor can you see if any of your large jumps are appearing larger than they may actually be? (It will be easier for you to try and look at them side by side).

I do think limiting the resolution to .1 dKH is a hinderance. Eventhough reading alkalinity in meq/L isn't our "norm" it would be a more definitive way showing alkalinity using this machine. (I know most people will frown at that thought).

 

[Rick.45cal]

I dunno, I've been thinking alot about that since you started posting your concerns.

Take my tank for example. I've chosen 7.5 as my setpoint. A number that isn't on the display. But I think the real question is how does the mathematics of the programming operate. I suspect that the actual device is not using dKH to do any of the calculations. But is then displaying that value times the conversion factor rounded to the tenth place in dKH. I think this is worth exploring. (Where's dr. Bridge when you need him).

If I changed my set point to 7.6dKH and my tank drops to 7.5 dKH and it is displayed as 7.4 dKH does the KHG then dose enough bicarbonate solution to increase by 0.1 dKH or does it dose the volume required to raise the tank 0.2dKH? I don't know which decision it would make in this instance.

 

[Rick.45cal]

In this page, your first jump from 8.0 to 8.3 (right where you have drawn the box) due to the mathmatics could be just a .1dKH increase (because 8.2 doesn't exist in the world of rounding). The 8.4 to 8.1 drop is another value that isn't exactly accurate if you do it via your meq/L spreadsheet then your drop isn't as significant. I do think reading alkalinity limited to a tenth place is a mistake, and this is the reason why it's a mistake.

The real question is what does the KHG do in these circumstances as to whether it is trustworthy. I would be interested to see a couple more days with your schedule recording the right times for the tests to see if it shows any correlation with your photoperiod or other environmental factors that you may spot.

It might be worth it, to allow it to dose, but send the bicarbonate solution back to the sodium bicarbonate vessel. Then you will get a recording in your log off how much it doses and when. Maybe make the maximum dosage that it makes .3 dKH and lets see if we can track what decisions it makes in regards to corrections. (Without you risking your system). That way maybe we can find some solutions to your answers.

I think you are right too about the range, you have increased the appearance of error in your test results because of the conversion factor! I happen to be missing less numbers (choosing one of the missing numbers has an advantage in that regard too)

 

[Jonty]

I am having Geos' reef build a custom box which will be really nice but that will take a while to receive.

 

[Rick.45cal]

Yes I updated time this morning. Rationally some of these numbers should be 8.2. But because it doesn't use then it looks like it's jumping up/down

I really do think that is a lot of what you are seeing.

 

[PedroYoung]

@Rick.45cal , @Jonty , @Sps3Sixty and others. Ups and downs, ins and outs, I'd like to thank all of you for contributing to the reefing community information pool. Great stuff, and thanks for the efforts.

 

[Rick.45cal]

Everyday at this time I feel strange, like I am forgetting to test my alkalinity.

 

[Rick.45cal]

Since I am not testing water I filmed a hermit crab huddle. (Pretty sure a mexican turbo bit the dust). Kind of unusual for me to see my two halloween hermits out in the front during the day. They seem most active at night. But it also looks like almost everyone showed up to the buffet! Escargot, anyone? (Excuse the crummy videographer, he is all I could afford on short notice )

 

[NCreefguy]

Everyday at this time I feel strange, like I am forgetting to test my alkalinity.

I'll send you a bottle of my tank water to test if it makes you feel better.

 

[NCreefguy]

Since I am not testing water I filmed a hermit crab huddle. (Pretty sure a mexican turbo bit the dust). Kind of unusual for me to see my two halloween hermits out in the front during the day. They seem most active at night. But it also looks like almost everyone showed up to the buffet! Escargot, anyone? (Excuse the crummy videographer, he is all I could afford on short notice )

Nice video...Makes me want to go clean my tank right now. Thanks a lot! lol

Do you take EVERYTHING out of your tank and clean it daily or what?

 

[Higher Thinking]

I'm not using the kh guardian to dose anything. I wanted to make sure that something measures accuratly/consistently before turning it loose on 75k of corals.
I am using a pretty reliable/consiatant masterflex dosing pump set at 60ml/min along with a reef octopus CR5000D, pH set at 6.6 I don't think you will get a much more stable environment.
It would take a significant event to cause a .3 drop/raise in a 400g system within 30 minutes. Which the kh has measured several times in the last 24 hours

I'm running 30 min tests, because if it was as accurate/consistsnt as claimed. There should not be any large dkh jumps on the 400g system. If it was set to 2 hours a large drop/raise would not be as significant. And the issue is more pronounced the more often tests are run.


Here is later in the day circled are multiple tests. If there wasnt multiple then I would just say it was just 1 test error. But it's not

What if you just took a sample of water and let it test it over the course of the day? Just keep it somewhere in the lower 70s to try and reduce the any precipitation. Theoretically, it should read a constant value all day. Perhaps a very slow drop if there is any precipitation, but even then, it would consistently be going down.

 

[samparker]

I am having Geos' reef build a custom box which will be really nice but that will take a while to receive.

Oh nice, hopefully they bring them to market!
I have to agree about displaying in DKH if it doesn't actually work in DKH is a bad idea. I'd happily work with Meg/L instead, especially if it's automated!

 

[Rick.45cal]

Nice video...Makes me want to go clean my tank right now. Thanks a lot! lol

Do you take EVERYTHING out of your tank and clean it daily or what?

Spit shined

 

[reeflover@hk]

This is interesting in my case compared with Rick.

Hanna measurement is more or less same as Salifert (Hanna ; 7.3 and Salifert 7.3 -7.7- 7.3 is noted as color. Start to change and 7.7 is that the color is not further pinker. ) KHG is 6.3.

With reference to the very consistent measurement of KHG, I decide to adj. the measurement by adding 1dKH.

@JonasRoman One of the checkers was brand new (hanna dKH meter), with new reagent. The other Hanna (ppm) was one I have used for 9 months or so, with reagent that hadn't been open more than 2 weeks. ( I test everyday, same methodology, same routine). The ppm meter never gives me the same answer twice, though it is always very close. The new meter reads 8.2 dKH no matter the sample I put in it. (From the ppm meter reading 138 ppm, dKH meter: 8.2 dKH).

Meanwhile Salifert KH titration yields a result every time that Hanna checkers are high by amost 1 dKH! Both hanna checkers read acceptable results for Hanna's alkalinity standards. Now maybe there was mishandling, it's always possible. But these readings fall within my ordinary readings. They are higher than I was trying to keep the tank (target of 7.5 dKH).

Based off of what I know, and had at my availability to test the checkers against suggests that they are wrong. Even the other checker agrees that the other hanna instrument is nearly .45 dKH off consistently from the other meter. For me, that's all I need to investigate this mystery.

Judging by my tank's inhabitants conditions, low alkalinity makes sense too me, and that's ultimately what made me decide to trust the KHG over the Hanna checkers (besides the fact that the Salifert titration consistently agrees with the KHG).

So there you have my reasoning for ditching the hanna checkers. I felt I was getting very precise (I wasn't), consistent readings (I was) from them, they were just very high (apparently). Shame on me for not cross checking with the Salifert titration constantly.

I'm not trying to bash Hanna Instruments, just share my experience, and reasoning as to why I have chosen to eliminate their use from my testing regime.