Help calculating Kalk dose for pH control

[aaron186]

I could use some help determining how to utilize kalkwasser via a kalk reactor in my tank

I have a 100 gal total volume tank that I’m using All for Reef to keep my Alk at 8.2-8.4. It’s working well but my pH isn’t great. Im running about 7.8-8.0 (verified my apex with Hanna checker that are both giving consistent results). My pH improves to 8.2 with a CO2 scrubber but I’m getting tired of dealing with the media. I can’t run a line outside or keep windows open. Already running a fuge. House has high CO2 levels. I can’t do lye due to small kids in the house.

I have an avast marine kalk reactor from an older tank that I want to use to help combat the pH. I was thinking of raising my Alk to 9 and running the reactor at night to combat the swings. I have no idea how to calculate how much kalk to add to the reactor and how fast to drip the RO into the reactor. Any advice or formulas would be greatly appreciated

 

[rishma]

I’ve been using kalkwasser on every tank for decades, and it helps nighttime pH a little, but not a lot, because the amount you can dose gets limited by evaporation or alkalinity demand. I expect you will find it has a lower impact than the CO2 scrubber.

I am not a fan of reactors so I cannot help much but there are calculators to help you understand the alkalinity dose of saturated kalkwasser. The amount you feed will be depending on how much alkalinity you want to add or how much evaporation you want to replace. You’ll need to reduce your AFR dose to keep alkalinity and calcium additions equivalent.

About 3.3 liters of saturated kalkwasser will add 1dKH to your 100 gallons.

Hope that helps.

 

[Amstar]

I use a motorized ball valve (3 way valve) that is controlled by my apex to help with my co2 and co2 scrubber. It shuts off and allows my skimmer to pull in fresh air when my ph gets to the level I want and then shuts a valve and pulls air through my co2 scrubber when the ph lowers

I actually just sold my avast marine kalk stirrer b/c dosing my 2 part and using my co2 scrubber (with the ball valve shut off) has kept things very level in the range I want

Have been able to keep my Co2 media last a lot longer and my ph very stable alone with my alk

Followed this here

Electronic ball valve for CO² scrubber

Ive seen ot of people using solenoids to control their ph.... i decided to try it with an electronic ball valve which did help some. But when the valve is open and drawing fresh air. It does still draw a small amount of air through the scrubber. I just found and set up a 3 way electronic ball...

www.reef2reef.com

 

[rishma]

I use a motorized ball valve (3 way valve) that is controlled by my apex to help with my co2 and co2 scrubber. It shuts off and allows my skimmer to pull in fresh air when my ph gets to the level I want and then shuts a valve and pulls air through my co2 scrubber when the ph lowers

Have been able to keep my Co2 media last a lot longer and my ph very stable alone with my alk

Followed this here

Electronic ball valve for CO² scrubber

Ive seen ot of people using solenoids to control their ph.... i decided to try it with an electronic ball valve which did help some. But when the valve is open and drawing fresh air. It does still draw a small amount of air through the scrubber. I just found and set up a 3 way electronic ball...

www.reef2reef.com

This really cool! I used a motorized ball valve back in the 90s as a wave maker for my closed loop.

I don’t use a scrubber so I am not sure what I’d apply this idea to, but I’ll perhaps I’ll be inspired for something. Thanks for sharing.

 

[Randy Holmes-Farley]

I don’t think calculating based on pH is useful. Dose to meet the alk demand, and you get what you get in terms of pH (which will never be too much in an aerated reef tank).