KH Guardian: Automatic Alkalinity Controller- My Experiences

[TD13]

I'm in.

 

[Mike810]

They say it's okay to dump back into the tank but I'm concerned there will be build up of whatever is in the reagent over time. I plan to measure how much tank water it uses after a test and simply have my AWC add that amount back in. The reason I asked about the long waste line is because I plan to run that line to a drain.

 

[AcroJack]

Any chance the new board will allow you to calibrate with 3rd party alk solutions like Triton 3a/b or Seachem Fusion?

 

[CoralWealth]

I am interested in getting one but how much do you guys think it will cost you every month to run it?

Regarding buying the regeant and so forth?

 

[AquaBelle]

Follow, Follow, Follow, Follow; Following Rick's KHG thread (road). By the way, I like your 1st sentence...very 'punny'(?)!

 

[Randy Holmes-Farley]

They say it's okay to dump back into the tank but I'm concerned there will be build up of whatever is in the reagent over time. I plan to measure how much tank water it uses after a test and simply have my AWC add that amount back in. The reason I asked about the long waste line is because I plan to run that line to a drain.

What you are adding back is zero alkalinity seawater. Nothing significant will accumulate if the acid used for the titration is adequately pure.

 

[chrissu]

Glad I found this thread!

 

[Rick.45cal]

I am interested in getting one but how much do you guys think it will cost you every month to run it?

Regarding buying the regeant and so forth?

So far I am still on my first batch of reagent

 

[Mike810]

What you are adding back is zero alkalinity seawater. Nothing significant will accumulate if the acid used for the titration is adequately pure.

That is great to hear. Now the question is, how pure is it??

 

[DavidUK]

What you are adding back is zero alkalinity seawater. Nothing significant will accumulate if the acid used for the titration is adequately pure.

I have been following along and find this very interesting, particularly with regards to adding the solution back to the tank.

Longer term isn't the addition of the "waste" to the tank going to cause some problems with the water? Assuming it is just acid that is being added to the tank water, what chemical changes will actually occur to the water?

Let me try to explain what I am thinking. Lets say the reaction chamber volume is 20mls, so each test will add back 20mls of tank water that has had pH reduced to 4.5 added back to the tank water. If we tested every hour, then 480mls per day of tank water would be "changed" as above. Extrapolating even further, (assuming no water changes) on lets say a 100 litre tank, then after just over 200 days, the whole of the tank water would have been through the KHG, with pH reduced to 4.5. Surely then, the tank water would have been massively changed?

It would be interesting if someone got a Triton analysis on their tank water and the "waste water" and compared them, I wonder what we would see?

 

[ryboy707]

Can't wait to see what neptune comes out with. I hope it comes soon or I might run out of patience and just grab one of these

 

[Randy Holmes-Farley]

That is great to hear. Now the question is, how pure is it??

I don't know, but there's no reason to think it less pure than the other additives you put into the tank at vastly higher amounts, like calcium and alkalinity additives. In terms of stuff added, 10 mL of zero alkalinity seawater added back to a 100 gallon aquarium would take about the same amount of solids added as boosting alkalinity by 0.0002 dKH. lol

Do you worry about the impurities in the alk additive you use at 10,000 times larger amounts?

 

[Randy Holmes-Farley]

I have been following along and find this very interesting, particularly with regards to adding the solution back to the tank.

Longer term isn't the addition of the "waste" to the tank going to cause some problems with the water? Assuming it is just acid that is being added to the tank water, what chemical changes will actually occur to the water?

Let me try to explain what I am thinking. Lets say the reaction chamber volume is 20mls, so each test will add back 20mls of tank water that has had pH reduced to 4.5 added back to the tank water. If we tested every hour, then 480mls per day of tank water would be "changed" as above. Extrapolating even further, (assuming no water changes) on lets say a 100 litre tank, then after just over 200 days, the whole of the tank water would have been through the KHG, with pH reduced to 4.5. Surely then, the tank water would have been massively changed?

It would be interesting if someone got a Triton analysis on their tank water and the "waste water" and compared them, I wonder what we would see?

This isn't rocket science. It is simple chemistry. No, it does not massively change. It changes so minimally you can hardly detect it. It effectively adds a tiny extra boost to alkalinity demand. In your example, 480 ml per day in a 100 liter tank boosts the apparent alk demand by 0.03 dKH. The pH effect is minimal. If aeration is complete, there will be no pH effect. If aeration is less than complete, the effect is small. I have shown that depleting alk by 1.4 dKH (with hydrochloric acid) instantly drops the pH by about 1.19 pH units. You are talking about 40 times less and spread out over the day. I'd be surprised if you could detect more than 0.02 pH unit drop in average pH.

We discuss these effects extensively in a thread in the chemistry forum with all of the folks that make the various automated alk devices. I might toss the waste too, but in reality it is not going to be a concern.

 

[Randy Holmes-Farley]

This is the thread I mentioned:

https://www.reef2reef.com/threads/kh-guardian-khg-alk-calculation.277092/

 

[justingraham]

Hey randy are u a scientist in real life and do you just relate your skills in this hobby?

Either way thank you for sharing ur brain with us

 

[Randy Holmes-Farley]

Hey randy are u a scientist in real life and do you just relate your skills in this hobby?

Either way thank you for sharing ur brain with us

Yes, I'm a professional chemist in drug discovery.

 

[justingraham]

Yes, I'm a professional chemist in drug discovery.

Well thank you for ur help there and on here

 

[eltonw]

You can choose 1 or 2 decimal from system setup and it will just show what you need on LCD.

 

[eltonw]

Is it what you need from KHG?
Yes, it is available now.

 

[Mike810]

I initially was planning to dump right back into the tank. Then I read everyone was dumping into a waste container instead. This makes me more comfortable dumping back into the tank when my tank is ready.