Dosing Kalk based on pH: 24 hour 9-16 Dkh

[c4haskett]

Just wanted to share my experience and wanted your thoughts. Two days ago once my pH hit its highest mark (8.3) I turned on Kalk dosing based on pH so its lowest point is set at 8.3. Yesterday it got up to 8.5. My Alk started at 9 dKh and landed almost up to 16 before maintaining. I did'nt know what kind of tank I would come home too but I've seen enough tanks dosed like this to atleast experiment with it myself. Surprisingly the tank looked... great?! Everything was open and polyps were super puffy and everything just looked happy?! This goes against everything I've ever learned about maintaining stable Alk. What are your thoughts about going forward with this method?

 

[Randy Holmes-Farley]

Two days ago once my pH hit its highest mark (8.3) I turned on Kalk dosing based on pH so its lowest point is set at 8.3.

What exactly does that mean? What happens if you go below 8.3?

High alk and high pH are not necessarily a problem, unless nutrients are low and you risk burnt tips, but raid alk changes do seem to be an issue. Soem corals seem to be fine at high alk, but perhaps not all.

One concern is greatly increased risk of precipitation of calcium carbonate at high pH and alk.

 

[Garf]

Just wanted to share my experience and wanted your thoughts. Two days ago once my pH hit its highest mark (8.3) I turned on Kalk dosing based on pH so its lowest point is set at 8.3. Yesterday it got up to 8.5. My Alk started at 9 dKh and landed almost up to 16 before maintaining. I did'nt know what kind of tank I would come home too but I've seen enough tanks dosed like this to atleast experiment with it myself. Surprisingly the tank looked... great?! Everything was open and polyps were super puffy and everything just looked happy?! This goes against everything I've ever learned about maintaining stable Alk. What are your thoughts about going forward with this method?

I imagine your test has incorporated some precipitation giving a super high reading. Unless you’ve added a load of Kalk, but in that case I’d have thought your pH would have been higher. Is the water a bit cloudy? Do you know how much Kalk it added? There’s a kalkulater (lol) that can work out expected alkalinity increases.

 

[c4haskett]

What exactly does that mean? What happens if you go below 8.3?

High alk and high pH are not necessarily a problem, unless nutrients are low and you risk burnt tips, but raid alk changes do seem to be an issue. Soem corals seem to be fine at high alk, but perhaps not all.

One concern is greatly increased risk of precipitation of calcium carbonate at high pH and alk.

To not cause to big of a ph change I waited for ph to hit its high for the day of 8.3. Once it hit 8.3 i dosed alk as to maintain that 8.3 throughout the low period. Once light comes on my ph crept up to 8.5. I will keep an eye on Calcium, thanks for letting me know that. My nutrients always stay pretty high, roughly 25-50 nitrate and .1-.25 phosphate.

 

[c4haskett]

I imagine your test has incorporated some precipitation giving a super high reading. Unless you’ve added a load of Kalk, but in that case I’d have thought your pH would have been higher. Is the water a bit cloudy? Do you know how much Kalk it added? There’s a kalkulater (lol) that can work out expected alkalinity increases.

I'm not sure how much it's actually dosing. It's enough that my ATO barely turned on. Water seems clear and calcium was around 500+.

 

[Garf]

I'm not sure how much it's actually dosing. It's enough that my ATO barely turned on. Water seems clear and calcium was around 500+.

Unless you’ve got a rediculously high evaporation rate, that would also suggest to me a testing malfunction, as long as your adding normal saturated and settled Kalk.

 

[c4haskett]

Unless you’ve got a rediculously high evaporation rate, that would also suggest to me a testing malfunction, as long as your adding normal saturated and settled Kalk.

My evap is not that high, im not sure the exact amount. I have been running a fan to increase evap amount. Kalk is fully saturated. Not dosing slurry or anything like that. My kalk doser has only been running from about 7pm to 9 AM. It does overfill a little bit but my salininty has still been in check. ATO cut on yesterday at 2pm. I tested several times and confirmed 16dkh

 

[exnisstech]

I have very limited experience but do drip kalk in one tank. I do not monitor but test several times a week. I'm dripping kalk 24/7 and can barely keep alk at 8.0 so I don't understand how dosing kalk could raise it to 16? I drip almost my evaporation rate and am currently dripping 6300ml of saturated kalk every 24hrs with a total water volume of aprox 220g.
Not doubting, this post is more of a question than a stamement.
EDIT : I rarely test pH but when I have it's always been 8.3 - 8.6

 

[Jason_MrFrags]

What was your normal tank ph running at?
Did your tank and corals look good?

Why are you hoping to accomplish with raising your tank ph?

 

[Randy Holmes-Farley]

I have very limited experience but do drip kalk in one tank. I do not monitor but test several times a week. I'm dripping kalk 24/7 and can barely keep alk at 8.0 so I don't understand how dosing kalk could raise it to 16? I drip almost my evaporation rate and am currently dripping 6300ml of saturated kalk every 24hrs with a total volume of aprox 220g.
Not doubting, this post is more of a question than a stamement.
EDIT : I rarely test pH but when I have it's always been 8.3 - 8.6

In a low demand tank, kalkwasser will raise alk and in a high demand tank, it won’t keep up.

 

[c4haskett]

I have very limited experience but do drip kalk in one tank. I do not monitor but test several times a week. I'm dripping kalk 24/7 and can barely keep alk at 8.0 so I don't understand how dosing kalk could raise it to 16? I drip almost my evaporation rate and am currently dripping 6300ml of saturated kalk every 24hrs with a total water volume of aprox 220g.
Not doubting, this post is more of a question than a stamement.
EDIT : I rarely test pH but when I have it's always been 8.3 - 8.6

TBH I'm not sure. I only have this experiment going in a 13.5 gallon tank with maybe 6 sps pieces. I don't have a high demand of alk to begin with. I don't know the science behind it but I tested once before at (9 dkh) and after 24 hours of dosing kalk to maintain 8.3 I was getting 15.8ish dkh using salifert. Tested twice. Test kit is good thru 27

 

[c4haskett]

What was your normal tank ph running at?
Did your tank and corals look good?

Why are you hoping to accomplish with raising your tank ph?

Normal PH was all over the place. I tried everything to stabilize. That being said we will go with an average of about 7.7 at night and 8.1 during the day. Corals did look fine before but growth was almost unoticeable in most pieces. I'm hoping to keep PH at a constant elevated level to increase coral growth. Eventually alk consusmption will increase, lowering the level that its at now and keeping the high ph benefits. Take a look at the ACI method on youtube.

 

[Jason_MrFrags]

Normal PH was all over the place. I tried everything to stabilize. That being said we will go with an average of about 7.7 at night and 8.1 during the day. Corals did look fine before but growth was almost unoticeable in most pieces. I'm hoping to keep PH at a constant elevated level to increase coral growth. Eventually alk consusmption will increase, lowering the level that its at now and keeping the high ph benefits. Take a look at the ACI method on youtube.

Almost impossible to keep ph from swinging. You can try to change the range that it operates in.
Exhaust fan or running an external air line for skimmer can help.
Careful with having an alk increase quickly and running it that high.
You can't just keep adding kalk trying to keep the ph up and allow the ALK to skyrocket off the chart. Needs to be a happy medium. When you find the balance you will probably find that it may only be giving you a .2 boost

I would also change it so your only using kalk during lights off.




Can you guess when all the people were over at the house for Halloween party?

 

[c4haskett]

Almost impossible to keep ph from swinging. You can try to change the range that it operates in.
Exhaust fan or running an external air line for skimmer can help.
Careful with having an alk increase quickly and running it that high.
You can't just keep adding kalk trying to keep the ph up and allow the ALK to skyrocket off the chart. Needs to be a happy medium. When you find the balance you will probably find that it may only be giving you a .2 boost

I would also change it so your only using kalk during lights off.




Can you guess when all the people were over at the house for Halloween party?

Lol I see!! Buddy i've tried everything in the book to raise Ph naturally. My tank sits directly beside a window. I installed a circulation fan in the window to blow fresh air right beside the tank... Did nothing! Also, the kalk is pretty much only dosing at night. It starts at around 7pm (lights out at 8) and ends around 9 am in the morning (lights on at 8). I'm keeping a close eye on everthing. I'm going to give it a few weeks and hopefully alk will have come down a little in that time.

 

[Randy Holmes-Farley]

TBH I'm not sure. I only have this experiment going in a 13.5 gallon tank with maybe 6 sps pieces. I don't have a high demand of alk to begin with. I don't know the science behind it but I tested once before at (9 dkh) and after 24 hours of dosing kalk to maintain 8.3 I was getting 15.8ish dkh using salifert. Tested twice. Test kit is good thru 27

To raise alk from 9 to 16 dKH in a 13.5 gallon tank will take 0.82 gallons of saturated limewater (kalkwasser).

Is your daily evaporation that high? I have no experience with tanks that small, but 6% daily evaporation is definitely in the very high end for most tanks.

It also likely will result in a big precipitation event if you keep adding that much.

 

[c4haskett]

To raise alk from 9 to 16 dKH in a 13.5 gallon tank will take 0.82 gallons of saturated limewater (kalkwasser).

Is your daily evaporation that high? I have no experience with tanks that small, but 6% daily evaporation is definitely in the very high end for most tanks.

It also likely will result in a big precipitation event if you keep adding that much.

You know what, I forgot to mention that I did about a 50% water change before starting this. I used RC salt and always use muriatic acid to get my alk around 9 before doing a WC. Since I knew i was about to start dosing the Kalk i did not do that this time. I usually get around 11-12 dkh in fresh mixed salt. I bet my ALk was already close to that before starting. My evaporation isn't that high at all. I don't know what it is exactly but I'd say it's close to 3 or 4 cups. The kalk did overfill passed my optical sensor but not enough to make impact on salinity so I think I'll be ok to continue doing this method, of course keeping a good eye on salinity and adjusting if need be.