How to do pH Control with Kalkwasser Dosing

[ReefStable]

Kick Your Reefing Game Up a Notch
Are you ready for the next level of reef tank dosing? Don't just maintain alkalinity, lock down your pH while you're at it!

ACI Aquaculture's pH Control with Kalkwasser Dosing

Learn how to amp up to the next level of reef keeping today!



This article is intended for intermediate to advanced reef keepers. Implement at own risk.

 

[Troylee]

Ive read this a few times and tried it once and my alk went up to 13 and I backed off… what I don’t understand is how they say dose twice what you evaporate? How am I suppose to keep my salinity up if I’m flooding the tank with kalk? I evap around 3-4 gallons a day on my tank so pumping 6-8 gallons of kalk is gonna start lowering my salinity a lot over a course of a week and on. Only thing I can think of is topping off with salt water but it would never kick on with the amount of kalk I’m putting in.

 

[Dburr1014]

Kick Your Reefing Game Up a Notch
Are you ready for the next level of reef tank dosing? Don't just maintain alkalinity, lock down your pH while you're at it!

ACI Aquaculture's pH Control with Kalkwasser Dosing

Learn how to amp up to the next level of reef keeping today!



This article is intended for intermediate to advanced reef keepers. Implement at own risk.

Bad idea.

 

[Jekyl]

@Randy Holmes-Farley thoughts?

 

[Dburr1014]

@Randy Holmes-Farley thoughts?

I know his thoughts on this, bad idea. He has posted on this before.

 

[Jekyl]

I know his thoughts on this, bad idea. He has posted on this before.

Thought so, wanted to bring him in either way.

 

[Dburr1014]

Thought so, wanted to bring him in either way.

I'll make the popcorn...

 

[Troylee]

Bad idea.

Not always! I know 2 tanks who are very successful running this way 1 is @Sisterlimonpot and his tank is rocking after he made his own controller, kalk reactor etc.. I’m sure there’s plenty more out there but nobody talks about it! The second one I know of is @Epic Aquaculture tank which was just tank of the month and insane! I wouldn’t say it’s bad I’d say more of a dangerous idea if you don’t know what you’re doing.

 

[Troylee]

I'll make the popcorn...

Also I’ve heard rumors for years that coral farms operate just this way and it’s been a trade secret.. I can’t confirm nor deny if it’s true or not.. lol

 

[Sisterlimonpot]

Yep, I've personally been doing this for 2 years. I suffered from 7.8 pH just like most hobbyists and never understood how people get their acros to grow so fast. Turns out pH is the key.

Although my method is slightly different than Chris Meckley's, the end results are the same.

I have my apex communicate with a custom kalk controller i made that incorporates a custom kalk reactor.

what I don’t understand is how they say dose twice what you evaporate?

I think that stems from getting around apex fusions native software. In fusion you're telling it to dose twice the amount, but because he suggest to only dose during a 12 hour period at night, it only doses half. It's just a clever way to overcome the hurdles in fusion.

I never really liked the DOS because of that reason. Which is partly why I made my own controller.

Chris Meckley seems to be dubbed the father of this idea. I was on a phone call with him a few weeks ago. It was interesting, when we were talking about elevated alkalinity, he peaked at 13.6 and when I went back into my logs, I noticed that I peaked at 13.6 as well. if Randy does chime in, I'd be curious if this is just coincidence or if there's something to hitting a alkalinity peak before precipitating.

Most people that I talk to gets scared when the alk gets above 10. I don't know what makes corals tolerate elevated alkalinity levels. I could only imagine that it has to do with the stable pH.

Here's a graph of the last 7 days on my tank pH.

I tested alkalinity yesterday and it is holding steady at 10.4.

Also I’ve heard rumors for years that coral farms operate just this way and it’s been a trade secret.. I can’t confirm nor deny if it’s true or not.. lol

This very well may be true, I 1st heard about it from one coral farmer, and then another. It made me sit up and pay more attention. I started to try and make the apex do what I wanted, the main draw back was not being able to read pH at the 12.44 range. That forced me to make my own circuit to talk to apex.

After I was doing it for a while, I found out that Chris has been basically doing it the same way with some slight differences.

I was glad I stumbled across him, it was a relief to read how he was experiencing most of what I was and that dispite obvious concerns he was letting it ride without any issue.

Is this for everyone? I would say, "absolutely not". There's so much that can go wrong, and I think you have to have some experience under your belt to spot any problems that may arise. I also think that a well stocked reef tank with adequate calcium carbonate demand needs to be established, or else you will start precipitating, which, I assume, is one of Randy's reasons for it being "bad idea".

Finally if I'm being honest, I think the corals are growing too fast. It's like playing a game and you discovered a cheat code... everyone knows, when you play a game using cheat codes, the thrill is no longer there.

I'll leave you with a visual of my tank. Note that 2 years ago my tank looked like most tanks starting out. A bunch of small frags glued to substrate.

 

[BigMonkeyBrain]

Randy said:
"PH

in seawater in equilibrium with the atmosphere, for a given alkalinity there is a single pH that results, regardless of what was added to get to that alkalinity. That is, it is only the amount of alkalinity added that determines the final pH, not the nature of the additive itself.

Here’s how to think of these additions. When these chemicals are added to the water, there is a change in the relative concentrations of carbonate and bicarbonate, and it is the ratio of these two ions that determines the pH."

 

[Epic Aquaculture]

Yep, I've personally been doing this for 2 years. I suffered from 7.8 pH just like most hobbyists and never understood how people get their acros to grow so fast. Turns out pH is the key.

Although my method is slightly different than Chris Meckley's, the end results are the same.

I have my apex communicate with a custom kalk controller i made that incorporates a custom kalk reactor.

I think that stems from getting around apex fusions native software. In fusion you're telling it to dose twice the amount, but because he suggest to only dose during a 12 hour period at night, it only doses half. It's just a clever way to overcome the hurdles in fusion.

I never really liked the DOS because of that reason. Which is partly why I made my own controller.

Chris Meckley seems to be dubbed the father of this idea. I was on a phone call with him a few weeks ago. It was interesting, when we were talking about elevated alkalinity, he peaked at 13.6 and when I went back into my logs, I noticed that I peaked at 13.6 as well. if Randy does chime in, I'd be curious if this is just coincidence or if there's something to hitting a alkalinity peak before precipitating.

Most people that I talk to gets scared when the alk gets above 10. I don't know what makes corals tolerate elevated alkalinity levels. I could only imagine that it has to do with the stable pH.

Here's a graph of the last 7 days on my tank pH.

I tested alkalinity yesterday and it is holding steady at 10.4.

This very well may be true, I 1st heard about it from one coral farmer, and then another. It made me sit up and pay more attention. I started to try and make the apex do what I wanted, the main draw back was not being able to read pH at the 12.44 range. That forced me to make my own circuit to talk to apex.

After I was doing it for a while, I found out that Chris has been basically doing it the same way with some slight differences.

I was glad I stumbled across him, it was a relief to read how he was experiencing most of what I was and that dispite obvious concerns he was letting it ride without any issue.

Is this for everyone? I would say, "absolutely not". There's so much that can go wrong, and I think you have to have some experience under your belt to spot any problems that may arise. I also think that a well stocked reef tank with adequate calcium carbonate demand needs to be established, or else you will start precipitating, which, I assume, is one of Randy's reasons for it being "bad idea".

Finally if I'm being honest, I think the corals are growing too fast. It's like playing a game and you discovered a cheat code... everyone knows, when you play a game using cheat codes, the thrill is no longer there.

I'll leave you with a visual of my tank. Note that 2 years ago my tank looked like most tanks starting out. A bunch of small frags glued to substrate.

 

[salty joe]

I'm confused, are people adding more kalk than their evaporation?
If so, that would mean draining water from the tank as well as adding salt, a steady water change.

 

[GlassMunky]

Thought so, wanted to bring him in either way.

yea curious to hear his thoughts in his own words since they quote him multiple times in the article

 

[aSaltyKlown]

How am I suppose to keep my salinity up if I’m flooding the tank with kalk? I evap around 3-4 gallons a day on my tank so pumping 6-8 gallons of kalk is gonna start lowering my salinity a lot over a course of a week and on.

I've been doing this for a year now and my salinity has been steady. I wouldn't say it's being flooded with kalk, it averages 640 mL in the 12 hours it runs, generally from 12AM to 12PM in 30 min intervals give or take an hour at times. That is about 0.16 gallons compared to my daily freshwater addition of 0.64gallons a day. The kalk solution basically works in conjunction with the ATO as a top off for the evap.

I have a 40 breeder with a 7g kalk reservoir that lasts about 3-4 weeks. My ATO reservoir is 5g that I need to top off every week or week and a half. The kalk is added overnight to maintain PH at 8.30.

My Alk is steady at 9.7 - it did spike up to 11 or so when I first started but came down after a month or so.

Two days of kalk dosing.

 

[Randy Holmes-Farley]

@Randy Holmes-Farley thoughts?

We have had extensive discussions of such ideas in the chem forum.

I do not recommend dosing calcium hydroxide or any hydroxide additive without at least once determining how high the alk can get after a while of using it, to see whether is it above what you want.

There are very clear scenarios where uncontrolled kalkwasser dosing (that is, not alk controlled) is not optimal, IMO. One is a tank with low alk demand and high home CO2 causing low pH. In that case, one can easily get the alk too high before reaching any predetermined pH target.

There are also obviously case where it works.

FWIW, I dosed kalkwasser only for 20 years. I consider it a very good choice for many reef tanks. But one needs to see what it does to alk. In my tank, I very rarely measured alk and only monitored pH because I knew that alk would not get too high because I initially monitored it. FWIW, I also did not control it by pH, I just used the pH to tell me if something was wrong, such as the ATO with kalkwasser in it had run dry or the tubing clogged.

Just an FYI, I did not watch the above video to see if it was discussed there, but kalkwasser is very slightly overbalanced to too much calcium relative to alk, and in many cases, it can lead to slightly rising calcium over time. I used a low calcium mix for water changes to offset that effect and it worked out fine.

 

[Randy Holmes-Farley]

I'm confused, are people adding more kalk than their evaporation?
If so, that would mean draining water from the tank as well as adding salt, a steady water change.

IMO, that's not the best plan. If you want to add more hydroxide than can be obtained from replacing all evaporated water with kalkwasser, I recommend to use a two part that uses hydroxide in addition to the kalkwasser (or instead of it).

The pH effect is the same and falling salinity is not a concern (rising salinity is, but that can be easily offset by removing some water if skimmers and other exports do not stabilize it adequately).

 

[Randy Holmes-Farley]

Chris Meckley seems to be dubbed the father of this idea. I was on a phone call with him a few weeks ago. It was interesting, when we were talking about elevated alkalinity, he peaked at 13.6 and when I went back into my logs, I noticed that I peaked at 13.6 as well. if Randy does chime in, I'd be curious if this is just coincidence or if there's something to hitting a alkalinity peak before precipitating.

Demand for alk and calcium rise as alk and pH rise. That's a negative feedback loop that will always limit how high alk and calcium can get in any given system when dosing more and more.

The tendency for precipitation of calcium carbonate increases as alk, calcium, and especially pH rise. At some point in elevating these, the always ongoing precipitation begins to overcome the tendency for things like phosphate, organics, and bacteria to coat new calcium carbonate surfaces and slow or prevent such precipitation.

Sometimes one just gets hardening sand and seizing pumps. That is the most common scenario when alk and pH rise slowly but steadily, and eventually the demand from precipitation and organisms will offset the additions, and alk will not rise more, and may fall.

But if these things are boosted fast enough, like in an alk overdose, one can gat a catastrophic precipitation event that turns the whole tank milky white with particles of precipitating calcium carbonate. That does not necessarily kill organisms because the negative feedback loop of the precipitation rapidly drops alk, calcium, and pH back toward normal. I had that happen a few times without losing anything (thought it is quite unattractive for a week or more).

 

[Randy Holmes-Farley]

Not always! I know 2 tanks who are very successful running this way

IMO, it's the "not always" that is the important point here, and in many aspects of reefing. It brings to mind a thread a while back, but can't currently find.

in any case, the idea is that folks need to be very careful when trying to duplicate anyone's success using only part of the methods they use. Yes, if you do everything the same, including the same air composition and the same organisms, you are very likely to have similar success.

But if you only opt to, or are only able to, duplicate part of the situation one may find the results are different or possibly very different.

Uncontrolled dosing of hydroxide in a system with high alk demand (so high it requires other methods at the same time) and normal CO2 in the air (which seems likely in a coral farm like ACI), the results may be very different in a system with low alk demand (such that replacing all evaporated water provides more alk than is demanded) and high home CO2.

Thus, in all cases, i urge reefers to be wary of picking and choosing parts of methods without considering what the implications of just using part of the methods might be.

 

[BigMonkeyBrain]

I'm confused, are people adding more kalk than their evaporation?
If so, that would mean draining water from the tank as well as adding salt, a steady water change.

I have watched this video before. He states to tell the controller to dose two times the amount of evaporation in 24-hrs but only have it dose 12-hrs at night ?

I am my controller - I would imagine it would be harder to acclimate corals to NSW parameters after the corals get used to higher PH and ALK ?

Randy said : "A drop from pH 8.5 to pH 8.2 is about 50% drop in carbonate."

Probably happens !

“So let it be written, so let it be done”