Kalk, Alk and the usual suspects =)

[JenDub]

Hey Randy,

I've been trying to get my main tank back on track. When I first tested a month or so ago my params were:

CA 300
mg 800
KH 13.9
ph 8-8.3
Salinity 1.021
temp 78-80

Needless to say I let maintenece go for a few months and things started to look unhappy. I read your article on bringing my ca up and alk down, I also started running my ca reactor, dripping kalk and dosing mg. I tested last night and my params were:

CA 430
MG 1320
KH 13.9
ph 8-8.3
Salinity 1.020
temp 78-80

I was wondering why my alk is so high? I'm a bit confused on how to tune my reactor to keep kh 8-10, I followed the manufacturer's advice and run the reactor 6.7-6.8 ph (probe in lid). I am also dosing kalk for the first time to keep ph up and I'm a bit confused on what I need to do to keep the parameters in range.

Any help would be much appreciated!

 

[Herpervet]

Hopefully Randy will chime in.

I would start by raising up your salinity closer to natural levels then go from there. You are using a refractometer right?

The alkalinity will come down if you ease up on the kalk and rely on the reactor alone. I don't think it's a problem at this point really.

I'm interested to see what Randy thinks will happen with your calcium etc. when you raise the sp. gravity to 1.026 since it is already so high.

I can't help but think you will get some precipitation (i.e. calcium carbonate) which would lower the alkalinity and calcium at the same time.

Then you start over at that point.

(But I'm just a spectator here )

 

[JenDub]

Yes, measured with a refracto. We ship a lot of stuff using this tank's water so the salinity slipped down lower than usual. It's usually 1.023

I took the kalk stirrer off the timer, hopefully that will calm things down for a bit...

 

[Randy Holmes-Farley]

I agree that bringing the salinity up would be good.

Drop the alkalinity by decreasing the CO2 sent to the reactor. Forget the pH, that is just rough guide territory. The tank alkalinity is the actual goal.

Everything will rise when you boost the salinity. A rise from a sg of 1.020 to 1.026 would boost all things by about 30%. So di it slowly and potentially allow calcium and magnesium to drop back.

 

[JenDub]

Awesome, Thanks Randy! I was wondering what I needed to dial back in order to get lower alk

 

[Randy Holmes-Farley]

:thumbsup:

Good luck.