Ph Pros - I need some insight

[BAUCE]

I've been running a new Icecap kalk reactor in hopes of stabilizing ph. It's rated for 200 gallons and is on my 120 gallon tank. I've been running it around 12 days so far and its been anything but stable.

You can see the ph going down day after day on the graph and then going up. That day I added almost half of what I initially started with less than 2 weeks ago. Is it normal to have to replenish kalk every few days to keep things from dropping off so fast?

 

[Kryptonian]

Water needs more oxygenation at night. That helped my similar problem a ton. You've got a ton of photosynthesis happening during the day then CO2 buildup at night.
Maybe reverse lighting with a refugium if you have one?

 

[BAUCE]

I understand why ph drops at night but I dont think that answers the question Im asking. Im wondering why it seems ph is dropping so much daily? Is this normal when using a reactor? I was under the impression that I would only need to add more kalk a couple times a month at most.

 

[Kryptonian]

Ya, a 0.3 swing day to night is decently large (I was doing the same thing). I don't have any experience using kalk, someone else will chime in there. What's going on with your alkalinity in comparison to ph?

I did start doing reverse lighting in addition to running a very small pump in the sump that had an air line launching bubbles around. That pump flips on at 9 pm and then off at 8 am. It made my swings go from 8.1-7.75 to 8.15-7.95.

I'm reading that dosing kalk as a 'right before bed' approach instead of during the day can help soften the curve. You might already be doing that.

 

[Randy Holmes-Farley]

I understand why ph drops at night but I dont think that answers the question Im asking. Im wondering why it seems ph is dropping so much daily? Is this normal when using a reactor? I was under the impression that I would only need to add more kalk a couple times a month at most.

Lack of complete aeration plus the consumption of CO2 by photosynthesis is the cause of the pH swing. Yours is not particularly unusual, but more aeration will reduce it, if you want.

As to the reactor, you didn't say anything about how much liquid you add tot eh tank each day, or what it's concentration is (measured by, say, conductivity).

 

[BAUCE]

Lack of complete aeration plus the consumption of CO2 by photosynthesis is the cause of the pH swing. Yours is not particularly unusual, but more aeration will reduce it, if you want.

As to the reactor, you didn't say anything about how much liquid you add tot eh tank each day, or what it's concentration is (measured by, say, conductivity).

I am adding a little over 50% of my evaporation daily that comes out to a little over a gallon (just following the directions). It’s being measured by my apex probe that was recently calibrated.

Do you think I could dose more? I understand the swings as those haven’t changed since adding the reactor. I’d just like to see the peaks and valleys stay consistently elevated for more than 2 days before coming down. I feel like I might not be expressing myself correctly here for some reason... that or I’m just confused

 

[Randy Holmes-Farley]

I am adding a little over 50% of my evaporation daily that comes out to a little over a gallon (just following the directions). It’s being measured by my apex probe that was recently calibrated.

Do you think I could dose more? I understand the swings as those haven’t changed since adding the reactor. I’d just like to see the peaks and valleys stay consistently elevated for more than 2 days before coming down. I feel like I might not be expressing myself correctly here for some reason... that or I’m just confused

If the concern is that the limewater is losing potency after 2 days, then you are either the stirrer is a poor design that is not stirring it adequately, or you are not adding enough.

If you are adding a gallon a day, then you could be consuming up to about 2 level teaspoons of solid material in a day. The mere presence of some solid material does not mean there is calcium hydroxide still present. There will be some insoluble material.