ALK Question Now that I fixed my low PH

Ericsch333 · Oct 14, 2014

What is a safe ALK swing though the day I tested 3 times yesterday.
Hanna
9:00 am 10.32 Alk
12:00 pm 9.84 Alk
6:30 pm 9.74 Alk I also tested CAL at 450-460 ( Red Sea) PH 8.08-8.20

I dose 2 part BRS (35 ml CAL and 35 ml ALK) I have a 90 gallon tank with 40B sump total water 110 gallons. My Apex dose the CAL in the day and the ALK at night the ALK stops 6:00 am. So does it look like I have it stable ? or do I need to still work on my ALK. The tank looks good and the corals seem happy.

Randy Holmes-Farley · Oct 14, 2014

That alkalinity swing looks fine to me, as long as it is not a ULNS SPS system.

Ericsch333 · Oct 14, 2014

No I am not running ulns but I have mostly SPS should I bring my ALK down more ?

tigerdragon · Oct 14, 2014

Alk looks fine just keep it stable

zemuss · Oct 14, 2014

Randy do you define a ULNS as a system which is dosing "something" to create the ULNS? or if I am running a ATS to achieve the ULNS that would be considered as well?

Ericsch333 · Oct 14, 2014

Thanks I have leaned a expensive lesson with ALK and Sps :cry: So if I can keep it between 9-10 that stable right.

zemuss · Oct 14, 2014

imo it depends on the system, like Randy stated.. In a ULNS the higher ALK levels will start burning your SPS corals. So I normally shoot between 8 to 9.

Randy Holmes-Farley · Oct 14, 2014

zemuss said:
Randy do you define a ULNS as a system which is dosing "something" to create the ULNS? or if I am running a ATS to achieve the ULNS that would be considered as well?

I do not know if ATS systems get to he point where it begins to starve zoox in corals, but I suppose it might.

Most often, it means carbon dosing of some sort, either DIY, zeovit, or other methods.

In any case, the thing that happens, as others have mentioned, is burnt tips. If you do not have that, then there's no need to worry.