george7523
22.02.2020, 00:22
Hi
A bit background on my experience with KH director so far.
got the kh director 3 months ago. Consistently had problems with inconsistent results since. (ie. sometimes closer to hanna within .1 dkh, sometimes as far as .8 dkh) An acceptable inconsistency would be if it were consistently x amount off. Then it would just be a simple matter of deducting or adding that to hanna results to ensure consistency. but it is consistently inconsistent.
I am very very very careful when doing hanna checking. (ie. no touching glass, always wipe sample bottle clean with tissue and lint free cloth, rinse and scrub inside with RODI after finish, always insert bottle same location before and after adding reagent) I am very confident in hanna results. And it correlates with effects of dosing. ie. if I dose 2ml alk, then measure 30 minutes later, then the Hanna alk reading increases a bit accordingly whereas KHD gets the same reading as before or even decreases.
On the Kh director end, I have followed all instructions (ie. flex pvc tubing for reagent, reagent intake tube is less then 1" long, used 50ml flask to calibrate pumps 2x each time I calibrate about once a month, calibrate PH)
I've been on reef2reef and other forums, its seems a number of people are having similar problems.
The following excerpts is taken from posting on reef2reef
https://www.reef2reef.com/threads/kh-director-about-as-useful-as-a-paperweight.544396/
the length of the cable is not set in the software properly.
A quick way to test if this is incorrect. if the KH director bubbles in the water after a test, from your intake on pump One, the calibration is a fail. If it bubbles more than 2 second ea 15-30 seconds , we have one of your issues.
My question is :
1. Is this a good way to test whether sample intake tube volume is set correctly ? the logic being if the pump continually attempts to push out water when it's already been emptied out then bubbles will be created. thus its best to keep bubbling to a minimum of 1 to 2 seconds ?
2. also, can you give instructions on how to remove the housing cover ? according to the same posting
There is a clamping tool in the back of the director which often causes quite a bit of trouble with the reagent chamber, I would suggest removing this and pressing it to make sure the air is not constricted. If it is restricted by the clamp, it could cause a lack of reagent and cause your readings to vary drastically each time.
and from another post
https://www.reef2reef.com/threads/ghl-kh-director-review.576407/
The older models had incorrect tubing for the reagent fluid - both internal tubing in the unit (which caused the tubing to get stuck and the unit would not work) and external tubing, which caused the reagent line to get air bubbles. GHL ultimately sent the correct tubing after a few weeks/months. If you have an older unit that has the incorrect tubing, you need to take apart the KH Director and replace the tubing. GHL has a good instruction packet to explain how to do this, but it's a pain.
Prior to replacing the internal tubing, the KH Director didn't work at all. The reagent line would pop off because the pressure of the incorrect tubing would case it to get stuck closed. After replacing the internal tubing, the KH Director worked, but the readings were very volatile (off by +/- 2.0 dKH when testing one right after another). This was due to air getting into the external reagent tubing. Due to the fact that these readings were so far off, I strongly recommend NOT using the auto-adjusting dosing feature based upon the dKH reading initially.
So I would like to remove the cover and check this out for myself. Maybe this would explain my problems.
Thank you
A bit background on my experience with KH director so far.
got the kh director 3 months ago. Consistently had problems with inconsistent results since. (ie. sometimes closer to hanna within .1 dkh, sometimes as far as .8 dkh) An acceptable inconsistency would be if it were consistently x amount off. Then it would just be a simple matter of deducting or adding that to hanna results to ensure consistency. but it is consistently inconsistent.
I am very very very careful when doing hanna checking. (ie. no touching glass, always wipe sample bottle clean with tissue and lint free cloth, rinse and scrub inside with RODI after finish, always insert bottle same location before and after adding reagent) I am very confident in hanna results. And it correlates with effects of dosing. ie. if I dose 2ml alk, then measure 30 minutes later, then the Hanna alk reading increases a bit accordingly whereas KHD gets the same reading as before or even decreases.
On the Kh director end, I have followed all instructions (ie. flex pvc tubing for reagent, reagent intake tube is less then 1" long, used 50ml flask to calibrate pumps 2x each time I calibrate about once a month, calibrate PH)
I've been on reef2reef and other forums, its seems a number of people are having similar problems.
The following excerpts is taken from posting on reef2reef
https://www.reef2reef.com/threads/kh-director-about-as-useful-as-a-paperweight.544396/
the length of the cable is not set in the software properly.
A quick way to test if this is incorrect. if the KH director bubbles in the water after a test, from your intake on pump One, the calibration is a fail. If it bubbles more than 2 second ea 15-30 seconds , we have one of your issues.
My question is :
1. Is this a good way to test whether sample intake tube volume is set correctly ? the logic being if the pump continually attempts to push out water when it's already been emptied out then bubbles will be created. thus its best to keep bubbling to a minimum of 1 to 2 seconds ?
2. also, can you give instructions on how to remove the housing cover ? according to the same posting
There is a clamping tool in the back of the director which often causes quite a bit of trouble with the reagent chamber, I would suggest removing this and pressing it to make sure the air is not constricted. If it is restricted by the clamp, it could cause a lack of reagent and cause your readings to vary drastically each time.
and from another post
https://www.reef2reef.com/threads/ghl-kh-director-review.576407/
The older models had incorrect tubing for the reagent fluid - both internal tubing in the unit (which caused the tubing to get stuck and the unit would not work) and external tubing, which caused the reagent line to get air bubbles. GHL ultimately sent the correct tubing after a few weeks/months. If you have an older unit that has the incorrect tubing, you need to take apart the KH Director and replace the tubing. GHL has a good instruction packet to explain how to do this, but it's a pain.
Prior to replacing the internal tubing, the KH Director didn't work at all. The reagent line would pop off because the pressure of the incorrect tubing would case it to get stuck closed. After replacing the internal tubing, the KH Director worked, but the readings were very volatile (off by +/- 2.0 dKH when testing one right after another). This was due to air getting into the external reagent tubing. Due to the fact that these readings were so far off, I strongly recommend NOT using the auto-adjusting dosing feature based upon the dKH reading initially.
So I would like to remove the cover and check this out for myself. Maybe this would explain my problems.
Thank you