Varied KH director readings

slosoak · May 5, 2019

i have a KH director that i have recently set-up. I would test twice a day and my readings were dropping over time, from 10 dkh to 6.5dkh. I got some help from the facebook group, mainly adjusting the waste water pump which i did and also making sure there is a clamp that pinch’s down at the beginning of a test which i have not checked yet. Since adjusting the waste water pump I get a reading of 8.5 which corresponds to a redseas test kit. Twelve hours later I get a reading of 6.7. I have not manually tested when getting the 6.5 reading. Next twelve hours it is back to 8.5 or so. Is there something specific I should check or do I need to remeasure and re calibrate? I posted in the GHL forum but have not received any replies.
Thanks

Ditto · May 7, 2019

slosoak said:
i have a KH director that i have recently set-up. I would test twice a day and my readings were dropping over time, from 10 dkh to 6.5dkh. I got some help from the facebook group, mainly adjusting the waste water pump which i did and also making sure there is a clamp that pinch’s down at the beginning of a test which i have not checked yet. Since adjusting the waste water pump I get a reading of 8.5 which corresponds to a redseas test kit. Twelve hours later I get a reading of 6.7. I have not manually tested when getting the 6.5 reading. Next twelve hours it is back to 8.5 or so. Is there something specific I should check or do I need to remeasure and re calibrate? I posted in the GHL forum but have not received any replies.
Thanks

I would first recalibrate the probe and make sure it is correct.

Are you doing any type of water changes at the time the KH is taking a reading?

If you move the test time say it was midnight and noon if you say 6:00am and 6:00pm does it do the same thing?

slosoak · May 7, 2019

Thanks for the suggestions. This does not occur during a water change. Test times are 8 am and 8pm, i will change times and see what happens. It is just weird that the morning readings are consistent with each other but different from the evening readings which are also consistent with each other

slosoak · May 7, 2019

Double post

DTE · May 10, 2019

I'm considering a kh director. Any update on this ?

slosoak · May 11, 2019

At this point no. I ran four tests within a two hour period and would get 8.3 then 4.6 then 10.4 then 4.8. I haven’t had the time to recalibrate everything, it is a process to set up. I have not received any responses from the GHL forum. Went back and forth with Vinny through e-mails but nothing of substance. After reading everything about the Trident and the support I received from Neptune with issues I may be going in that direction. The problems I am having seem pretty consistent to indicate a specific problem but the best solution suggested was to recalibrate the pH probe so far.

slosoak · May 11, 2019

Ditto said:
I would first recalibrate the probe and make sure it is correct.

Are you doing any type of water changes at the time the KH is taking a reading?

If you move the test time say it was midnight and noon if you say 6:00am and 6:00pm does it do the same thing?

Ran four tests within a two hour period and would get 8.3 then the next test was 4.6, next 10.4then the next 4.8. Haven’t had a chance to recalibrate the pH probe, hopefully this weekend

Ditto · May 11, 2019

It should not be fluctuating this much. Are you seeing any air bubbles in the Solution line?

slosoak · May 11, 2019

There are none.

slosoak · May 11, 2019

Ditto said:
It should not be fluctuating this much. Are you seeing any air bubbles in the Solution line?

There are none. It is weird the fluctuation is so consistent

kodo28 · May 12, 2019

Check everything again,

- Perform a calibration of each head with a gram scale 5 times then calculate arithmetic average. Eliminating the highest and lowest recorded results you’re left with 3 results, add them and divide by 3 to get the arithmetic average. Once done ask to dose a specific amount on each head to check the accuracy of each head.

- Monitor each of your tests 8AM/8PM for any air bubble on the reagent tubing if you can.

- Make sure that you are not taking the water sample near of your ATO or any source of other liquid dosing.

- Make sure that the end of the tubing from where you are taking water is not to deep in water and it is taking clean water with any debris.

- Check for any pinched tubing on your installation

- Verify the water sample settings on GHL Control Center they should be 100% accurate with the length of your water sample tube.

- Verify that the waste water tubing is not hang in the water

Can you post some pictures of your installation

slosoak · May 12, 2019

kodo28 said:
Check everything again,

- Perform a calibration of each head with a gram scale 5 times then calculate arithmetic average. Eliminating the highest and lowest recorded results you’re left with 3 results, add them and divide by 3 to get the arithmetic average. Once done ask to dose a specific amount on each head to check the accuracy of each head.

- Monitor each of your tests 8AM/8PM for any air bubble on the reagent tubing if you can.

- Make sure that you are not taking the water sample near of your ATO or any source of other liquid dosing.

- Make sure that the end of the tubing from where you are taking water is not to deep in water and it is taking clean water with any debris.

- Check for any pinched tubing on your installation

- Verify the water sample settings on GHL Control Center they should be 100% accurate with the length of your water sample tube.

- Verify that the waste water tubing is not hang in the water

Can you post some pictures of your installation

Afraid you were going to suggest this. Time lately has not been my friend

Brew12 · May 12, 2019

What is your dosing schedule, dosing product, and water volume?

slosoak · May 12, 2019

My doser is not connected to the KH director. I dose two part 4 times a day, 15 ml a dose. It is a reefer 170 mixed reef so not a big tank. I had been using Red Sea but been seeing a lot of precipitate in the bottles so switched back to ESV.

slosoak · May 12, 2019

kodo28 said:
Check everything again,

- Perform a calibration of each head with a gram scale 5 times then calculate arithmetic average. Eliminating the highest and lowest recorded results you’re left with 3 results, add them and divide by 3 to get the arithmetic average. Once done ask to dose a specific amount on each head to check the accuracy of each head.

- Monitor each of your tests 8AM/8PM for any air bubble on the reagent tubing if you can.

- Make sure that you are not taking the water sample near of your ATO or any source of other liquid dosing.

- Make sure that the end of the tubing from where you are taking water is not to deep in water and it is taking clean water with any debris.

- Check for any pinched tubing on your installation

- Verify the water sample settings on GHL Control Center they should be 100% accurate with the length of your water sample tube.

- Verify that the waste water tubing is not hang in the water

Can you post some pictures of your installation

The unit is in the basement. Do have a question, i have 38ml in the water sample line, i use a 80ml sample so does it matter how accurate the sample water line is as long as the water sample taken is larger?

Brew12 · May 12, 2019

slosoak said:
The unit is in the basement. Do have a question, i have 38ml in the water sample line, i use a 80ml sample so does it matter how accurate the sample water line is as long as the water sample taken is larger?

I believe it does matter. If you put more water into the measuring chamber than calculated it will take more reagent to lower pH and cause a reading to be higher than actual.