Kalk vs refugium

allof fish

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Trying to decide whether to run Kalk at night to boost ph or add a refugium. Currently running 2 part and use about .7-.8 dkh a day so not entirely sure if consumption is enough for kalk. Main goal is to increase ph drop at night. Currently with a co2 scrubber ph peaks around 8.3ish but still drop to 8 or even a little under at night. If adding a fuge or kalk how much can I expect to stabilize ph at night? Which option may be best and if kalk what’s best way to achieve ph boost without over increasing alk at night. Thanks all
 

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Easy answer, do you need a nutrient reduction or will a reduction in nutrients cause issues? Personally I run both and rarely if ever ever see a PH drop below 8.3 even in the dead of winter.
 

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Trying to decide whether to run Kalk at night to boost ph or add a refugium. Currently running 2 part and use about .7-.8 dkh a day so not entirely sure if consumption is enough for kalk. Main goal is to increase ph drop at night. Currently with a co2 scrubber ph peaks around 8.3ish but still drop to 8 or even a little under at night. If adding a fuge or kalk how much can I expect to stabilize ph at night? Which option may be best and if kalk what’s best way to achieve ph boost without over increasing alk at night. Thanks all
Without knowing significantly more variables there is no way to accurately answer your question. How large is your system volume? How much water does your tank evaporate per day? Do you know what your co2 is in your home? Does that number fluctuate significantly over a 24 hour period?
There are more things that need considered than this but my fingers are tired from typing a wall of text and you can do further research.
Easy answer, do you need a nutrient reduction or will a reduction in nutrients cause issues? Personally I run both and rarely if ever ever see a PH drop below 8.3 even in the dead of winter.
Not an easy answer at all. See above.
 
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Easy answer, do you need a nutrient reduction or will a reduction in nutrients cause issues? Personally I run both and rarely if ever ever see a PH drop below 8.3 even in the dead of winter.
I don’t need a nutrient reduction as even water changes sometimes mess with them,nutrients aren’t very high nitrate around 10 phos .07-.1. Also looking for easiest method without messing with major elements. I know if I go Kalk way I’ll likely have to decrease my 2 part dosing a good amount
 
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allof fish

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Without knowing significantly more variables there is no way to accurately answer your question. How large is your system volume? How much water does your tank evaporate per day? Do you know what your co2 is in your home? Does that number fluctuate significantly over a 24 hour period?
There are more things that need considered than this but my fingers are tired from typing a wall of text and you can do further research.

Not an easy answer at all. See above.
Water volume just shy of 100. Not entirely sure on evaporation or co2 levels. I was not going to add Kalk to ato. Ph fluctuates at night but I do not know co2 levels
 

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Most people see co2 drop starting when everyone leaves the house in the morning, and begins to rise at the end of the day when they return. If you want to run kalk, you can help stabilize your daily evaporation by running a dehumidifier at, say, 50% RH. Your indoor humidity might fluctuate considerably depending on seasons/weather. If you let it go naturally, your evaporation will swing wildly depending on environmental factors. With a refugium you see a gradual increase in effectiveness as your algae mass grows in size, then a sharp drop when you harvest. It's a cycle you have to be aware of if you are really chasing that pH number.

Just some more things to think about in your quest. I personally run kalk at night because I'm already dosing significant po4 daily to keep up with my coral demand.
 
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If I put Kalk in ato and dosed what im evaporating how much of a ph boost could that be. I’m assuming it will stabilize it pretty well. Then I can continue my 2 part of that is not enough. Does kalk produce the same ratio or alk and calcium?
 

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You're asking a question that I can't answer. You have to know your starting ph, and the amount of evaporation losses you are replacing with saturated kalkwasser solution. Saturated kalk is pH 12. If you can determine exactly how much top-off water you are adding, you can do the math to figure out the expected pH rise.
 

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Not an easy answer at all. See above.
You provide great information but IMO are over complicating it. OP just needs to raise his PH 0.3-0.4 overnight and when you're ask which one or the other, you look at the largest difference between the two. If OP already has issues with nutrients then obviously a refugium is out of the question. It really is that easy to answer OP's question. However, once you answer that question that's, how to best implement adding ALK to OP's tank without causing issues with their current 2-part dosing regime. That is where your information comes into play.

OP, if you're really looking for a simple answer to raising your PH without causing a disruption in your dosing regime, get a large (or a couple) Pothos or a Snake Plant next to the aquarium. I live in a fairly rural community but even I saw a large jump in PH when we started keeping house plants, and mine are only in the room adjacent to my aquarium. If you don't have a lot of windows in the room, you can always buy a $15 plant light from amazon and you'll be good to go. Worst comes to worst, if you don't see a change, at least you have some nice new decor!
 

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What are you dosing for 2part? Switch to a greater PH boosting method
 

Doctor Derp

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You provide great information but IMO are over complicating it. OP just needs to raise his PH 0.3-0.4 overnight and when you're ask which one or the other, you look at the largest difference between the two. If OP already has issues with nutrients then obviously a refugium is out of the question. It really is that easy to answer OP's question. However, once you answer that question that's, how to best implement adding ALK to OP's tank without causing issues with their current 2-part dosing regime. That is where your information comes into play.

OP, if you're really looking for a simple answer to raising your PH without causing a disruption in your dosing regime, get a large (or a couple) Pothos or a Snake Plant next to the aquarium. I live in a fairly rural community but even I saw a large jump in PH when we started keeping house plants, and mine are only in the room adjacent to my aquarium. If you don't have a lot of windows in the room, you can always buy a $15 plant light from amazon and you'll be good to go. Worst comes to worst, if you don't see a change, at least you have some nice new decor!
Respectfully.. this is not the hobby for guesswork. Lives are quite literally on the line. Overdosing kalkwasser is a good way to wipe out a system.
 

Randy Holmes-Farley

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I agree that switching to a higher pH two part will help.

I suspect the refugium will have a larger effect than the small amount of kalk mentioned. One can make that as large as you want.
 
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allof fish

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Respectfully.. this is not the hobby for guesswork. Lives are quite literally on the line. Overdosing kalkwasser is a good way to wipe out a system.
Would a smart way and also a safe way be this…. I was thinking about getting a trident potentially. I could put Kalk into my ato around lower to middle of the dosage amount. I will replenish what I evaporate, not entirely sure the amount but around .3-.5 gallons a day I assume. With the trident testing alk 4 times a day and my ph probe I can monitor my ph which should be boosted from the kalk day/night and assuming that’s not enough I can also run my 2 part as well. Once I get it down to know how much my tank uses of the kalk a day I can supplement the rest of alk and cal from my 2 part. This would be a safe way to keep ph high from kalk while also keeping alk steady from multiple daily testings and dosing from my dos
 
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allof fish

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I agree that switching to a higher pH two part will help.

I suspect the refugium will have a larger effect than the small amount of kalk mentioned. One can make that as large as you want.
Any other brands of high ph 2 part. Also could my idea above be possible? Refugium currently i believe will just strip my nutrients as small water change do so too.
 

Randy Holmes-Farley

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Any other brands of high ph 2 part. Also could my idea above be possible? Refugium currently i believe will just strip my nutrients as small water change do so too.
There are commercial hydroxide versions, but also diy alk parts which are otherwise the same as the BRS recipe.

With a refugium that was scaled up, you’d want to dose N and P if those are low. That is not expensive, but does involve testing.
 
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allof fish

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There are commercial hydroxide versions, but also diy alk parts which are otherwise the same as the BRS recipe.

With a refugium that was scaled up, you’d want to dose N and P if those are low. That is not expensive, but does involve testing.
At this time I have to dose nitrates sometimes if they get too low. Ideally looking for the most consistent cost effective way to raise ph consistently. With fuge need light and algae but seems easier than kalk since that affect alk and calcium. Which would you recommend for consistency of both parameters and higher ph?
 

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Respectfully.. this is not the hobby for guesswork. Lives are quite literally on the line. Overdosing kalkwasser is a good way to wipe out a system.
I didn't say dose willy nilly and I didn't say guess. I said a direct answer to the question asked is easy. The question of how to implement is much more complicated and requires further questions and answers.
 
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Do we think adding a fuge it better if I have to dose nitrates and phosphates if needed instead of messing with kalk which dosing 2 part. If a fuge a night will limit my ph drop to .1-.2 instead of .3 or higher that is a win. Ph in day would also probably climb higher since it takes all day to get to the 8.3 ish from the morning low. Instead of messing with Kalk this option is good while keeping alk stable. Any thought?
 

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