What do you run your ALK at?

[dlemonz]

Curious to see what people run their ALK at. I typically run it at 10 dKH and had a lot of success with that. However, i met an OG this weekend who runs it at 7.5 and had an awesome looking tank!

 

[Randy Holmes-Farley Verified Community Expert]

I recommend 7-11 dKH, and all values in that range work. :)

 

[Science/G]

I like it around 8.5 FWIW

 

[exnisstech]

Im an 8.5 dkH guy give or take a little either way.

 

[BriDroid]

7.8-8.0

 

[Reginald Reefer III]

~9.0-9.3. I run my nutrients a bit higher (~25ppm NO3 and ~0.15ppm PO4) so run my alk a bit higher.

 

[Red_Beard]

7.5 - 8.5 but I shoot for 8.0

 

[LavenderTi]

8 ish in my Display Tank. Sometimes as low as 7.3 and as high as 8.2.

My coral QT however is as low as 4-5 since I don’t test regularly. Slow adjustments to get back up to 8. Corals all look happy even at the low values.

 

[56longroof]

9.3

 

[Pistondog]

7.5 to 8.5, prefer 8 and above.

 

[areefer01]

I recommend 7-11 dKH, and all values in that range work. :)

I guess we need to let Fiji know they need to dose alkalinity ;) I am teasing as I'm sure ATI ICP numbers can be off a bit.

Measurement	Fiji (December 13, 2024)
Salinity (PSU)	35.33
Carbonate hardness (dKH)	6.85

 

[Randy Holmes-Farley Verified Community Expert]

I guess we need to let Fiji know they need to dose alkalinity ;) I am teasing as I'm sure ATI ICP numbers can be off a bit.

Measurement	Fiji (December 13, 2024)
Salinity (PSU)	35.33
Carbonate hardness (dKH)	6.85

Yes, I’m aware the ocean is a bit lower. :)

 

[VintageReefer]

8.25 but I’ve been considering raising to 9 due to higher nitrate and phosphate

 

[areefer01]

Yes, I’m aware the ocean is a bit lower. :)

I was honestly teasing and also know it isn't your first rodeo :)

 

[penfold2]

What is the rationale behind running alk proportional to nutrient levels? Is it maximizing growth potential by eliminating one or the other as a bottleneck?

 

[VintageReefer]

What is the rationale behind running alk proportional to nutrient levels? Is it maximizing growth potential by eliminating one or the other as a bottleneck?

My understanding is higher alk can yield faster skeletal growth rates, but then higher nutrients are needed for coral flesh growth to keep up

In sps growth a common problem is “white tips” or “burnt tips” and it’s been found one cause is high alk / low nutrients. The skeleton grows slightly faster than the flesh and then can appear as white tips, or grow algae and appear as burnt tips

 

[dlemonz]

i have found regardless of what i keep it as long as i keep it all within 0.5 dkh day to day everything seems pretty happy

 

[skey44]

7.5 - 8.5 but I shoot for 8.0

I’m here too, I run this range because I use Tropic Marin Pro Reef and that is the alkalinity it mixes at. So this alk range promotes stability when changing water. Of note if kH is drifting I monitor it daily and try to make sure the swing is very slow. Then I dial in my afr dose to try and get back to 8 slowly. This is for Acropora coral. I’m sure my diligence isn’t necessary for certain types of corals, though my LPS certainly don’t mind the stability.

 

[edsbeaker]

I’m in that 8.5 range.

 

[Laith]

7.5