Kalk supplementing a carxm how?

[natas]

Ok first things first, I am a master at over complicating things in my head. I often overthink things instead of keeping it simple.

I got a 260G. I use a Calcium Reactor to maintain Calcium and Alk. Things have been running smoothly. When I set the reactor up over a year I noticed (as many here know) my PH running low. In fact it has always been on the low end (modern home, well sealed yada yada). So I setup a CO2 scrubber and for the past year its done a pretty good job but over time the demand from my corals has become more and more. So with the demand comes more CO2 to feed reactor to maintain...and you guessed it very low PH. Last week I hit a new low of 7.65 and I am now maxing at 7.85.

Here is what I am trying to wrap my head around.

So....I am now thinking I have no choice but to start supplementing with Kalk using a Kalk Reactor. My brain is confused as to how I can maintain a consistent ALK and Calcium level. Right now my ato is setup to run as many times a day as it has to limiting itself to run no longer then 25 minutes and also minimizing changes to PH. Now here's the deal..... Evaporation is not consistent, I haven't measured anything but I am sure some days are worse then others (heater, chiller, ac running etc).

How do you guys control alk swings. I get you can limit on PH but what if I have a high day of evaporation and have to dump twice as much saturated Kalk then I did the day before?

 

[chema]

Calculate the maximum evaporation rate per day you have. That shall be your kalk adition limit. Then use your kalk reactor, a dosing pump, a programer and the reposition water to add kalk at set intervals and during set periods of time so as to add a volume always lower than the limit previously calculated. Dose preferentially at night, when pH reaches the its lowest. In this way you would be adding a fixed amount of kalk per day.
Next task is to calculate the KH needs of your tank and supplement the kalk adition with your calcium reactor, thus fulfilling those needs.
Good luck and enjoy your tank

 

[bknapp]

I also run a kalk reactor and calcium reactor. The best and easiest way to dose kalk on a consistent basis is to program a dosing pump, I'm using a BRS pump to feed my Avast reactor plugged into my Apex. I dose once an hour and stir once an hour and just use top off water to feed it. You'll end up topping off less due to actually dosing.

 

[Randy Holmes-Farley]

Ok first things first, I am a master at over complicating things in my head. I often overthink things instead of keeping it simple.

I got a 260G. I use a Calcium Reactor to maintain Calcium and Alk. Things have been running smoothly. When I set the reactor up over a year I noticed (as many here know) my PH running low. In fact it has always been on the low end (modern home, well sealed yada yada). So I setup a CO2 scrubber and for the past year its done a pretty good job but over time the demand from my corals has become more and more. So with the demand comes more CO2 to feed reactor to maintain...and you guessed it very low PH. Last week I hit a new low of 7.65 and I am now maxing at 7.85.

Here is what I am trying to wrap my head around.

So....I am now thinking I have no choice but to start supplementing with Kalk using a Kalk Reactor. My brain is confused as to how I can maintain a consistent ALK and Calcium level. Right now my ato is setup to run as many times a day as it has to limiting itself to run no longer then 25 minutes and also minimizing changes to PH. Now here's the deal..... Evaporation is not consistent, I haven't measured anything but I am sure some days are worse then others (heater, chiller, ac running etc).

How do you guys control alk swings. I get you can limit on PH but what if I have a high day of evaporation and have to dump twice as much saturated Kalk then I did the day before?

Limewater will likely be a minor component to your total additions of alk so the swing will not be big, but you can put the limewater on timed delivery to be just below demand on typical days rather than ATO if you prefer.

 

[2una]

Can i ask what is probably a stupid question plse:
I'm in a similar situation to the OP - already taken other measures to get my ph as high as i can.This is including running 3 skimmers in my sump to offset the carbonic acid.(all with outside airlines)
I'm managing 7.8-8.1 with all these measures but 3 skimmers running to do it is a pretty sad joke.
I use a Dastaco carx - its PH is unadjustable & coming out of the 2nd chamber is still a Ph of 6.1 (this effluent already drops into 1 cupless skimmer)

What chemistry nightmare is going to happen if i were to feed the effluent thru a kalk stirrer?.
I'm going to get precipitate happening yes?
BUT
With the Dastaco it as a 1/10 dial to increase effluent , I'm only currently sitting at 1.5/10 so i have plenty of room to increase output.
Would it be likely i could override the level of precipitate to maintain my tank where it needs to be or is the effluent all just going to collapse once the Co2 rich/low ph effluent hits the kalk solution?
Co2 & kalk aren't exactly buddies are they?
Is it likely to just try turning the kalk into a block?

I know the "normal" way would be to just try feed the kalk unit separately but wondering what would happen if it was done this way.

 

[Randy Holmes-Farley]

Can i ask what is probably a stupid question plse:
I'm in a similar situation to the OP - already taken other measures to get my ph as high as i can.This is including running 3 skimmers in my sump to offset the carbonic acid.(all with outside airlines)
I'm managing 7.8-8.1 with all these measures but 3 skimmers running to do it is a pretty sad joke.
I use a Dastaco carx - its PH is unadjustable & coming out of the 2nd chamber is still a Ph of 6.1 (this effluent already drops into 1 cupless skimmer)

What chemistry nightmare is going to happen if i were to feed the effluent thru a kalk stirrer?.
I'm going to get precipitate happening yes?

Definitely. Not ever a good idea. Even running normal tank water through it is a disaster as magnesium hydroxide will precipitate.

 

[Randy Holmes-Farley]

Feeding the reactor output into the skimmer might be more effective.

 

[2una]

Feeding the reactor output into the skimmer might be more effective.

Yes thats where its dropping into already,into a cupless one

Definitely. Not ever a good idea. Even running normal tank water through it is a disaster as magnesium hydroxide will precipitate.

Okay thanks so mag falls out
Randy is that likely to be a total fallout or something akin to iron/iodine disappearing where we could dose some to hold an acceptable level?

 

[Randy Holmes-Farley]

Yes thats where its dropping into already,into a cupless one



Okay thanks so mag falls out
Randy is that likely to be a total fallout or something akin to iron/iodine disappearing where we could dose some to hold an acceptable level?

It would be a disaster with massive precipitation. lol
It will also be unbalanced, effectively swapping in a calcium for each magnesium it removed as magnesium hydroxide. It will also precipitate calcium/magnesium carbonate.

 

[2una]

Okay thank you, that's what i wanted to hear - enough warning shots to cross that plan off the list,cheers

 

[Randy Holmes-Farley]

Okay thank you, that's what i wanted to hear - enough warning shots to cross that plan off the list,cheers

You're welcome.

Are you replacing all evaporation with saturated limewater?

 

[2una]

You're welcome.

Are you replacing all evaporation with saturated limewater?

No i've not involved kalk in the equation at all yet as i didn't want to open up alk instability issues but it looks like i'm heading there.
I tried a 3rd chamber already & for some reason it buffered for about 12 hours then went back down to 6.1 as well so i'm kind of lost on ideas where to go next.

 

[Randy Holmes-Farley]

In most cases where folks use a reactor and limewater, the reactor adds most of the calcium and alkalinity, and the limewater, while adding some, is just there to mostly boost pH.

If alk stability is very important to you, you can put the limewater on a dosing pump to dose most of the daily water evaporation, and use an ATO or manual to keep it the rest of the way topped off. :)

 

[2una]

In most cases where folks use a reactor and limewater, the reactor adds most of the calcium and alkalinity, and the limewater, while adding some, is just there to mostly boost pH.

If alk stability is very important to you, you can put the limewater on a dosing pump to dose most of the daily water evaporation, and use an ATO or manual to keep it the rest of the way topped off. :)

Yep - kalk stirrer on dosing pump is i think the next logical move...thank you for your time Randy.
When you get bored please invent us a carbonic acid eater