Kalk and Soda Ash

[AC545]

I recently changed up my dosing hoping to achieve greater stability. My tank is now less stable, Alk swings roughly 1 dkh per 2-3 days according to my trident.

230 gallon system, mostly frags and small lps colonies
Ph 7.7-8
Alk 9-10 dkh
Calcium 440-390
Mag 1460-1450
Everything else is stable and in acceptable ranges.

After installing a Neptune DOS I removed Kalkwasser from my ATO. I am dosing 1,000 ml evenly through a 24 hour period. Hoping to boost Alk I am also dosing 40 ml of Soda Ash while the lights are on. My tank has little swings throughout the day, .2 dkh. It also has greater swings over the course of 2-3 days 9-10 dkh.

Should I abandon Soda Ash and strictly dose Kalkwasser?
What is considered stable dkh thoughout the course of a day? Throughout a week?

 

[cilyjr]

Only you can decide what to do. I do what you are doing and have been since I abandoned the calcium reactor a couple of years ago.

My alkalinity fluctuates from about 9.2 to 9.8.
It does not go in in a steady rate and I allow the Trident to control the dosing.

What I mean is more kalkwasser is added during the peak photoperiod than in the morning or at night.

What you need may be more or less and even may require more scheduled periods.

I'm using a kalk reactor for space saving purposes but a bucket could be used just the same.

The Trident control dosing is actually a pretty intelligently designed system. It nots a simple turn on or off if a number is achieved or needs to be, but rather a system that adjusts percentages. Look into it! I do manual testing roughly weekly with salifert to confirm trident numbers.
Here is an example of Neptune Tridents controlled dosing.

You can see the target is 9dkh
If it's out of range by + or - .5 dkh the system will in crease or decrease the dosed amount by 30%. All of these are user set parameters.

To answer whether you need both. I do not add much of the sodium carbonate (soda ash) it's a small buffer, when I was in the 320 gallon, before this tank, my demand was exceeding evaporation so I was required to use more sodium carbonate there, wine the 500 fills out I will likely have to use much more. So it will depend both on system demand, evaporation, and personal preference.

Hope that helps.

 

[AC545]

Thank you, I got this from google AI, is this true?

Kalkwasser and soda ash instability usually results from rapid pH increases triggering chemical precipitation of calcium carbonate, leading to cloudy water, clogged pumps, and unexpected alkalinity/calcium drops. Because kalkwasser has a high pH (12+) and soda ash is highly alkaline, combining them or dosing too quickly causes a, "snowstorm" effect where minerals fall out of solution.

 

[cilyjr]

Thank you, I got this from google AI, is this true?

Kalkwasser and soda ash instability usually results from rapid pH increases triggering chemical precipitation of calcium carbonate, leading to cloudy water, clogged pumps, and unexpected alkalinity/calcium drops. Because kalkwasser has a high pH (12+) and soda ash is highly alkaline, combining them or dosing too quickly causes a, "snowstorm" effect where minerals fall out of solution.

I mean maybe if you were dripping both of them into the same area like an inch apart.

 

[luu78]

Have you considered reverse photoperiod dosing to narrow down your pH range/swing? I typically dose most of my alkaline solutions (kalk/alk) right before the light goes off and throughout the night. Then I typically dose any acidic solution (vinegar dosing) during the bulk of my photo period when pH is typically higher to minimize pH drop. This seems to help and my alk stays quite stable I would say. Good luck and hopefully you find what works for your system soon.

 

[JBendel]

My two cents.... simplify ... dose Soda Ash and Calcium chloride and you can dial in your Alk and Calc levels, and PH will more or less take care of itself. You may have other variables that I am unaware, so buyer beware.