KH Director Help

[VJV]

Hi,

After two months of working relatively well my KHD started acting up late last night and I hope my SPS will survive it, given I was using Adaptive Control mode. For two months I have had relatively constant readings, within +/- 0,1dKh of my Hanna Checker... that is, if you can call +/- daily swings of 0,5-0,9dKh stable, in spite of the adaptive dosage. Testing 12x per day and dosing 12x per day as well, so I expected the kHD to smooth out the daily swings much better. But I digress. last night I got a reading of 14dKH just before going to bed (what else...). I had just recently changed the reagent and calibrated the pH probe (and tested the calibration to be spot on) so I was a bit concerned... I could not see how in just 2 hours the tank had shot up to 14dKH so I canceled the adaptive mode and went to sleep (by late I mean 2am). This morning I got my trusty Hanna out and as expected, my dKH was actually at 8,2 while the KHD still showed 14,6dKh.. I went on to calibrate the sample and reagent pumps (as well as cleaning them because they were filled with a thick black powder and squeeking a bit. I guess with 12 tests a day and a sample of 80ml for 2 months has had a toll on the Doser 2.1 heads. After disaembling the dosing heads, cleaning them, putting back together, calibrating them, I ran a test and 8,2dKH poped up. Good, I thought, can go back to work. At the end of the day I get another warning with a dKh of 6.6!!!! Again, when arriving home tested with the Hanna and it was reading 8,3dKh.

I already opened a ticket with GHL but if anyone can chip in it would be most appreciated, as currently my kHd and Doser 2.1 are a couple of very expensive paper weights...

(I also have a P4, several sensors, GHL Breeze, another Doser 2.1 etc, so not exactly new to GHL. Also worth noting that I am running the KHD off of my Doser 2.1 stand alone)

Many thanks!

 

[fcmatt]

Gosh it is stories like this which keeps me from buying any alk testing/dosing setup. Too much money for such headaches. Following.

 

[Cali9dub]

Hi,

After two months of working relatively well my KHD started acting up late last night and I hope my SPS will survive it, given I was using Adaptive Control mode. For two months I have had relatively constant readings, within +/- 0,1dKh of my Hanna Checker... that is, if you can call +/- daily swings of 0,5-0,9dKh stable, in spite of the adaptive dosage. Testing 12x per day and dosing 12x per day as well, so I expected the kHD to smooth out the daily swings much better. But I digress. last night I got a reading of 14dKH just before going to bed (what else...). I had just recently changed the reagent and calibrated the pH probe (and tested the calibration to be spot on) so I was a bit concerned... I could not see how in just 2 hours the tank had shot up to 14dKH so I canceled the adaptive mode and went to sleep (by late I mean 2am). This morning I got my trusty Hanna out and as expected, my dKH was actually at 8,2 while the KHD still showed 14,6dKh.. I went on to calibrate the sample and reagent pumps (as well as cleaning them because they were filled with a thick black powder and squeeking a bit. I guess with 12 tests a day and a sample of 80ml for 2 months has had a toll on the Doser 2.1 heads. After disaembling the dosing heads, cleaning them, putting back together, calibrating them, I ran a test and 8,2dKH poped up. Good, I thought, can go back to work. At the end of the day I get another warning with a dKh of 6.6!!!! Again, when arriving home tested with the Hanna and it was reading 8,3dKh.

I already opened a ticket with GHL but if anyone can chip in it would be most appreciated, as currently my kHd and Doser 2.1 are a couple of very expensive paper weights...

(I also have a P4, several sensors, GHL Breeze, another Doser 2.1 etc, so not exactly new to GHL. Also worth noting that I am running the KHD off of my Doser 2.1 stand alone)

Many thanks!

might be a silly question but did you make 100% sure you had no bubbles in the reagent tubing when you swapped it out?

 

[VJV]

might be a silly question but did you make 100% sure you had no bubbles in the reagent tubing when you swapped it out?

Thanks. I do not believe I do... and the calibration of the pump is spot on... i will check it again today in any event.

 

[VJV]

Gosh it is stories like this which keeps me from buying any alk testing/dosing setup. Too much money for such headaches. Following.

When it works it is the best thing ever. You find out things you would not imagine. In my tank I found out that I have a very big daily swing, likely due to the fact of very high variation in CO2 levels in the living room where the tank is. We have 4 kids so at night and in winter the CO2 levels go beyond 1.000ppm, pushing pH down. During the day with everyone away and open windows CO2 levels drop to 400ppm, pH goes up to 8,4 8,5. My Alk consumption during the night is almost zero while during the day it shots up. When the KHD is working i am able to smooth out these peaks and the corals responded immediately. Also when I increased slightly my photo period with a longer night mode at just 10% intensity much to my surprise consumption shot up during that time.

The KHD caught these changes up and kept up with the demand.

When it works, it is awesome. When it soes not work it cam kill your tank if you are not careful.

 

[Tristren]

If you have black buildup in the dosing heads they are rubbing against the casing. If the heads are sticking it could throw everything off. It almost sounds like you have an old doser from when they were having those issues (there was a manufacturing issue with one of the parts at one point). Or the rollers are just not pushed in enough.

Clean the heads and lubricate with a bit of Vaseline. Make sureeverytthing is really really in place.
But definitely a ticket is the way to go as that's not normal.


Cheers, Tony

 

[VJV]

If you have black buildup in the dosing heads they are rubbing against the casing. If the heads are sticking it could throw everything off. It almost sounds like you have an old doser from when they were having those issues (there was a manufacturing issue with one of the parts at one point). Or the rollers are just not pushed in enough.

Clean the heads and lubricate with a bit of Vaseline. Make sureeverytthing is really really in place.
But definitely a ticket is the way to go as that's not normal.


Cheers, Tony

Thanks Tony,

I know about the old Doser. I have one of those too and in the past GHL sent me a couple of replacement heads a couple of years ago for that one for exactly the same reason. This doser came with the KHD+Doser package I bought some 5 months ago so I would expect the doser to be a new one. Unfortunately, much like the old doser this one also seems to have problems. I will try to lubricate the heads. Exactly where do you apply the vaseline? To the tube, the rollers?

Having said this, if the calibration of the pumps is spot on in theory the measurements should be accurate, at least initially... I will give it a try.

 

[Tristren]

As I understand it the lubrication is a thin film inside the blue casing.
Weird that you have build up on a new unit though. And you said it is just two of the heads?

What did support suggest?

I have very similar dosers as you btw. Got one back when they had issues. Replacement heads have worked perfectly ever since. Got a new one with a KHD last month. No issues with that one though.

Tony

 

[VJV]

As I understand it the lubrication is a thin film inside the blue casing.
Weird that you have build up on a new unit though. And you said it is just two of the heads?

What did support suggest?

I have very similar dosers as you btw. Got one back when they had issues. Replacement heads have worked perfectly ever since. Got a new one with a KHD last month. No issues with that one though.

Tony

yes. The unit is fairly new, but these two heads (sample and drain) each pull about 1.000ml per day while the reagent one max 36ml. So these work a lot harder and hence the reason (I think) why they are the ones having this buildup.

i am still going back and forth with an open ticket for this responses have not been too helpful. “Have you read the manual” or the “FAQ section”type of thing.

 

[Dr. Jim]

You should only lubricate the "prongs" that the rollers slip over. If you get lubricant on anything else, it will eventually get on the rollers and they will slip when the metal spinning "rod" tries to turn them. (I made this mistake and had to replace the whole unit!)

 

[VJV]

You should only lubricate the "prongs" that the rollers slip over. If you get lubricant on anything else, it will eventually get on the rollers and they will slip when the metal spinning "rod" tries to turn them. (I made this mistake and had to replace the whole unit!)

Whoa ! Had no idea that I could ruin the whole unit simply by lubricating the wrong part... good to know. Thanks!
I guess by prongs you mean the three plastic “shafts” (for lack of a better word) that go into each roller...?

 

[Kyl]

Yes

 

[fcmatt]

Seems all the solutions to the problem point at the dosing pump and not the director.

 

[VJV]

Seems all the solutions to the problem point at the dosing pump and not the director.

One does not work without the other so to me they are a package. Not really concerned about which part is not working (other than to find the right solution).

 

[fcmatt]

One does not work without the other so to me they are a package. Not really concerned about which part is not working (other than to find the right solution).

I meant more along the lines of I am taking a mental note that the doser seems to be the most common culprit. No suggestions on the director itself.

Ghl for automation is my current possible choice to purchase in the near future so I read these threads like a hawk.

Could a tube not be inserted into the director properly which is sucking in air?? Could something be loose inside the director? Like slipping apart?

 

[VJV]

I meant more along the lines of I am taking a mental note that the doser seems to be the most common culprit. No suggestions on the director itself.

Ghl for automation is my current possible choice to purchase in the near future so I read these threads like a hawk.

Could a tube not be inserted into the director properly which is sucking in air?? Could something be loose inside the director? Like slipping apart?

Not really. The thing worked well for about 4 months than all of a sudden readings spiked all over the place. I am inclined to having a bad Doser, like the ones that came out a couple of years ago (I know because I bought one of those too... ) which had a problem regarding premature wearing of the dosing heads... there is a lot of dust inside the two heads that work the hardest (sample and flush) ao I am incluned to that being the case. The problem is that I am getting readings of 7,1 dKh to 8,1 during the day while the Hanna checker remains relatively stable between 8,4 and 8,6. If the difference was constant it would not be an issue but this is a real issue because I cant trust the results I am getting from the khd, which renders it useless...

(Not to mention that my GHL equipment (P4 and SA Doser) keep loosing the wifi connection several times per day so a lot of times I cant even see what os going on... )
I never used another system so do not know if they all have all these glitches but I must warn you that it can be very frustrating at times.

 

[Cali9dub]

I get some wonky readings from my KHD when my skimmer foam collapses and sends a bunch of micro bubbles into my Sump where the KHD collects samples. Goes from 9.0 to 6.2 then back to 9.0 after a few tests and turning the skimmer off while the KHD is sampling. So now I am going to have to program my skimmer to be off just before the KHD samples (6 times a day) and turn back on about 15 minutes after the sampling starts. It’s always something !!

 

[VJV]

I get some wonky readings from my KHD when my skimmer foam collapses and sends a bunch of micro bubbles into my Sump where the KHD collects samples. Goes from 9.0 to 6.2 then back to 9.0 after a few tests and turning the skimmer off while the KHD is sampling. So now I am going to have to program my skimmer to be off just before the KHD samples (6 times a day) and turn back on about 15 minutes after the sampling starts. It’s always something !!

That is amazing!!! I probably would have never thought about that. Thanks for sharing!

 

[Michael Gray]

i have the new doser with KH.... its a few months old only ... my squeeks and then locked up... i bought new rollers and caps... within like 2 weeks.. the pump that drains the KH squeeked again.. i just cleaned it.. tube is black.. rollers get black.. i have a new unit.... i was told bascially i gotta replace it.. so i guess i need a pallet of rollers and covers. and every two weeks gotta swap em out... nonsense.. im not happy about that part...

but i would double check calibration and length of tubing from draw... also placement of the filter and where it draws from. @AZMSGT helped me awhile ago with it. filter at the end... i put it in betwen baffles..

 

[Michael Gray]

it took me a long time to get mine pretty dialed... but i think also helps is just keep running it... dont have it on adaptive mode for awhile.. just have it read for a month or so maybe

i do love the KH though... im just not a fan of the Dosers...i feel they are flawed..

just need a dang Po4, and no3 auto tester and id be pumped... Tired of testing po4 lol