KH - What’s the Magic # and WHY!?

[EakTheFreak]

Howdy Reefers,

What is the magic number for KH and why?

Please list your current KH and these other major parameters and explain how you decided on your KH.

KH - ?
Salinity - ?
CAL - ?
MAG - ?
Phosphate - ?
Nitrate ?

Here is mine:
KH - 10.0
Salinity - 1.025
CAL - 475
Mag - 1450
Phosphate - .05 - .08
Nitrate - 10 ppm

I run my KH @ 10.0 because it increases my PH especially in winter months in Cleveland, OH when I can’t count on fresh air to raise the PH of the tank. I tend to run everything a bit higher due to this.

 

[OREGONIC]

I shoot for 7.8-8.0, if Im in that range I dont make any corrections to my calcium reactor. Its rare my tank falls outside 7.5-8.2. I use Red Sea blue bucket salt which mixes in the 7.8-8.0 range, that is the main reason I run my tank there. Its nice to know if I ever need to do a large water change I wont have any major alk fluctuations.

Salinity 1.026
CAL 400 - 425
MAG 1350 - 1450
Phosphate .02 - .05
Nitrate 3 - 7

 

[ZoWhat]

Chasing Alkalinity is like chasing your body temp thruout the day.... sometimes your body temp is in the 97s, other times in the 99s


.

 

[EakTheFreak]

Chasing Alkalinity is like chasing your body temp thruout the day.... sometimes your body temp is in the 97s, other times in the 99s


.

What range do you run yours at?

 

[TexanCanuck]

I (try) to keep my KH @ around 8.5 based on Randy Holmes-Farley's article here:

Optimal Parameters for a Coral Reef Aquarium: By Randy Holmes-Farley

[note: last updated edited on 8/10/2022] One of the main roles of an aquarist with a coral reef aquarium is to ensure that the conditions are right for their tank inhabitants. There are many different attributes of the aquarium that need to be...

www.reef2reef.com

In summary, the goal is to keep alkalinity high enough to help corals build mass, while not being so high as to accelerate precipitation on pump impellers and other equipment.

Here's how my alkalinity varies throughout a few days, compared against when I dose liquid soda ash (green line disappeared today once I figured out how to setup up "controlled dosing" with my Trident!)

Other key water parameters:

pH - 8.1 to 8.3
Salinity - 1.025
Calcium - 400ppm
Magnesium - 1300ppm
Phosphate - 0.03ppm
Nitrate - 2ppm

 

[JCM]

Consistency is the magic number.

 

[ZoWhat]

What range do you run yours at?

Dont know, don't care.... bc I have mostly zoas/palys. If I had a bunch of God-awful Acros, different story. Lol

I do an dKH test maybe 3x a year. And usually only if I see polyps struggling.

Most times btwn 8-10

I will say this: you start dosing and screwing around with your Alk, you will set yourself up for headaches, crashes, coral dying. Just my experience


.

 

[arking_mark]

I think it's all relative to your overall approach to reefing. I think stability is actually the key.

I have higher CO2 in my house, which means I want to use dosing that increases pH like kalkwasser. So I focus on pH and dialing in Alk at something reasonable that gives me wiggle room to increase/decrease dosing to keep things stable. So something around 8.5 would be probably my ideal.

 

[EakTheFreak]

I (try) to keep my KH @ around 8.5 based on Randy Holmes-Farley's article here:

Optimal Parameters for a Coral Reef Aquarium: By Randy Holmes-Farley

[note: last updated edited on 8/10/2022] One of the main roles of an aquarist with a coral reef aquarium is to ensure that the conditions are right for their tank inhabitants. There are many different attributes of the aquarium that need to be...

www.reef2reef.com

In summary, the goal is to keep alkalinity high enough to help corals build mass, while not being so high as to accelerate precipitation on pump impellers and other equipment.

Here's how my alkalinity varies throughout a few days, compared against when I dose liquid soda ash (green line disappeared today once I figured out how to setup up "controlled dosing" with my Trident!)

Other key water parameters:

pH - 8.1 to 8.3
Salinity - 1.025
Calcium - 400ppm
Magnesium - 1300ppm
Phosphate - 0.03ppm
Nitrate - 2ppm

Thanks for sharing this. Very interesting.

 

[krash7172]

Dont know, don't care.... bc I have mostly zoas/palys. If I had a bunch of God-awful Acros, different story. Lol

I do an dKH test maybe 3x a year. And usually only if I see polyps struggling.

Most times btwn 8-10

I will say this: you start dosing and screwing around with your Alk, you will set yourself up for headaches, crashes, coral dying. Just my experience


.

Sounds a bit strong but I'm in your camp. I'm steady around 9.0 with water changes and mostly softies. I only test monthly.

 

[Born2beblack]

Huh im curious cause iam just starting to dose and i know what i use daily in consumption
But would this be okay
Whatis a good idea to shoot for

Salinity - 1.025
CAL - 460
MAG - 1410
Phosphate - ? Need new test i ran out
Nitrate 20 or a bit lower hard ro say

Lowering nitrates and raising alk is my first mission

 

[krash7172]

Testing is how to determine your tanks consumption. All tanks are different and they change as corals grow.

 

[EakTheFreak]

Huh im curious cause iam just starting to dose and i know what i use daily in consumption
But would this be okay
Whatis a good idea to shoot for

Salinity - 1.025
CAL - 460
MAG - 1410
Phosphate - ? Need new test i ran out
Nitrate 20 or a bit lower hard ro say

Lowering nitrates and raising alk is my first mission

What are you lowering your nitrates with? NoPOX?

 

[nereefpat]

I will say this: you start dosing and screwing around with your Alk, you will set yourself up for headaches, crashes, coral dying. Just my experience

That's a really strange opinion. Most reefers are stony coral keepers that have to dose alk.

 

[josvanmeer]

ALK uptake is directly related to your Phos and Nitrates. You have to keep it balanced. Corals use nitrates and Alk to grow. If you run an ultra low nutrient system (ULNS) then you keep your Alk lower in the 7 to 8 range because if you force your coral to grow faster they simply can't, since the nitrates are gone at that point. I keep my Alk around 9-9.5 and nitrates around 10-15ppm. As long as you balance and stabilize your Alk and Nitrates, you can keep it whatever number.

 

[Auquanut]

I auto dose Alk and Cal due to the high consumption in my heavily stocked mixed reef. Manually dose Mag.

PH - 8.1 to 8.3
KH - 8.5 to 9.0
Salinity - 1.026
CAL - 420 to 440
MAG - 1400 A little high for me. letting it fall slowly to hopefully 1350ish.
Phosphate - .08
Nitrate 16ish

I've been getting some GHA for a while now. May adjust my NO3 and PO4, but I'll do it slowly and hopefully without using chemicals or GFO.

 

[Born2beblack]

What are you lowering your nitrates with? NoPOX?

Im not using any chemicals or anything

I just monitor my feedings and reef roids amount
Wont happen any time soon but each month im going down about 2.5ppm
I was at 25 months ago now i sit around 15 or less
Mid spring im hoping to be at 10 which is perfect for what i wanna do.

 

[PBnJOnWheat]

Howdy Reefers,

What is the magic number for KH and why?

Please list your current KH and these other major parameters and explain how you decided on your KH.

KH - ?
Salinity - ?
CAL - ?
MAG - ?
Phosphate - ?
Nitrate ?

Here is mine:
KH - 10.0
Salinity - 1.025
CAL - 475
Mag - 1450
Phosphate - .05 - .08
Nitrate - 10 ppm

I run my KH @ 10.0 because it increases my PH especially in winter months in Cleveland, OH when I can’t count on fresh air to raise the PH of the tank. I tend to run everything a bit higher due to this.

In my opinion, it’s more about stability than the numbers. My all just happened upon 10 so I keep it there LOL so far so good!

 

[dvgyfresh]

I aim for 9 , I feel like it gives me wiggle room if I don’t dose for a little bit and likewise if I overdose it won’t rise too far

 

[EakTheFreak]

I aim for 9 , I feel like it gives me wiggle room if I don’t dose for a little bit and likewise if I overdose it won’t rise too far

Yes, I’m debating on slowly dropping myself down to 9 as well just to dose less. My PH will be higher with natural air with the weather getting better as well!