Dosing Kalkwasser at night

[Swordsman82]

Hello all

Like everyone around here I am guessing, tank is not having the highest PH right now. Currently dosing Fauna Marin balling and using a CO2 scrubber. My PH is a low of 7.85 at night to a high of 8.15 during peak photo period. Coral colors are looking great, so I don't want to change out to an entirely different dosing system. But the Sodium Bicarbonate doesn't boost my PH at all. Wanna try running Kalkwasser at night to stabilize PH, and slow / stop the drop in PH. Hoping to get closer to 7.95-8 PH minimum at night

Anyone have any experience with this or how to set it up?

I noticed that from lights off to just before light on my tank doesn't even use Alk (tested multiple times and i have gotten a .1 difference which is with in error range of Hanna checker), do you slow drip a lot at night making it the main Alk/Calc driver for the tank?

 

[SteveDola]

Reefbum has a basic setup to employ (Google it). I’d run on a doser with a bucket of a mix of kalk and ro starting when the lights go off until the morning.

 

[DatReefGuy]

Had decent luck with dosing for pH and Alk. I mainly did mine for Alk but as you can tell I need to dose more. Lol. The lowest I get down to for pH at night is 7.71 and Alk I usually never get above 7.0. Even when I do dose more. The doser I use is the 1.1mL per minute from BulkReefSupply. I do intend to dose more after I get a bigger container for kalk.

 

[dz6t]

How about use sodium carbonate instead of bicarbonate for Alk? Carbonate boosts the pH a little. Kalkwasser is a good choice to boost pH.

 

[DatReefGuy]

And adding a CO2 Scrubber will give a little bit of a pH boost.

 

[Swordsman82]

And adding a CO2 Scrubber will give a little bit of a pH boost.

I currently have a CO2 Scrubber hooked up. Which is probably saving my PH from really bottoming out. Tank is in living room in a house with 2 adults, 3 kids, 2 dogs, and grandparents visiting constantly. CO2 Monitor is always reading off the charts lol

 

[jayteerq]

I dose about 7200mL a day in a kalk stirrer. At first it was an even dose for 24 hr. But now I’m slowly adding onto night dosing and decreasing into day dosing to see if I can get fluctuations in alk and ph at a minimum. I struggled with low PH too between 7.7-7.9 but am now hovering between 8-8.3

 

[Swordsman82]

How about use sodium carbonate instead of bicarbonate for Alk? Carbonate boosts the pH a little. Kalkwasser is a good choice to boost pH.

I thought about trying Sodium Carbonate. Not sure about how it would work if I mixed it with Sodium Bicarbonate or the Trace Elements mixed in with it. Or just changing over to straight Sodium Carbonate will upset anything. All my corals have been coloring up really well, specially my Acros starting to come around. I figured low dose of Kalkwasser at night would not do a huge amount to upset the tank

 

[Swordsman82]

I dose about 7200mL a day in a kalk stirrer. At first it was an even dose for 24 hr. But now I’m slowly adding onto night dosing and decreasing into day dosing to see if I can get fluctuations in alk and ph at a minimum. I struggled with low PH too between 7.7-7.9 but am now hovering between 8-8.3

Okay so you are using Kalk as your main driver for Alkalinity and Calcium, right? You do you see a spike in Alk at night from Coral not up taking it?

 

[Swordsman82]

Reefbum has a basic setup to employ (Google it). I’d run on a doser with a bucket of a mix of kalk and ro starting when the lights go off until the morning.

Thank you, I will check it out

 

[dz6t]

I thought about trying Sodium Carbonate. Not sure about how it would work if I mixed it with Sodium Bicarbonate or the Trace Elements mixed in with it. Or just changing over to straight Sodium Carbonate will upset anything. All my corals have been coloring up really well, specially my Acros starting to come around. I figured low dose of Kalkwasser at night would not do a huge amount to upset the tank

Sodium carbonate and bicarbonate can’t be mixed with many trace elements except iodide and fluoride. Only dose it alone.
Mixing trace elements with major elements such as calcium is a big no, as the consumption rates are dramatically different. You will overdose trace elements and most of the metals are toxic when overdosed.

 

[jayteerq]

Okay so you are using Kalk as your main driver for Alkalinity and Calcium, right? You do you see a spike in Alk at night from Coral not up taking it?

I also dose 40mL of AFR evenly every 24. Not sure why but all my dips occur at my 12 AM test.

 

[Swordsman82]

Sodium carbonate and bicarbonate can’t be mixed with many trace elements except iodide and fluoride. Only dose it alone.
Mixing trace elements with major elements such as calcium is a big no, as the consumption rates are dramatically different. You will overdose trace elements and most of the metals are toxic when overdosed.

I do the Fauna Marin Balling which has their Trace 3 that gets mixed with Bicarbonate. Its Potassium, Sodium Fluor, Iodine, Bromine. It's a fairly small amount, 25ml of their Trace 3 elements per 5 Lites of Bicarbonate solution.

Currently my PH is a fairly gradual curve with the photo period. Increasing with lights coming on, peaking around mid-photo period, leaving out, then slowly ramping down till lights out. Then it just keeps going down till next day's Photo period. I am dosing 45mls of Bicarbonate over 11 doses thru out the day, and you there is barely noticeable shift in the PH. Would changing over to Sodium Carbonate create spikes in PH during the day?

 

[dz6t]

Using carbonate won’t spike the pH, it will keep the pH slightly higher.

 

[dz6t]

Also, if your coral are doing great, I won’t worry about the pH, the APEX pH probe is pretty bottom barrel despite its cost. Take the pH absolute value as a slightly larger grain of salt.

 

[Kens Bees]

Also, if your coral are doing great, I won’t worry about the pH, the APEX pH probe is pretty bottom barrel despite its cost. Take the pH absolute value as a slightly larger grain of salt.

I run two separate cheapo ph probes. They consistently show about 0.15 apart from each other, rain or shine. What they’re good at is showing trends. You can tell exactly when I dose at night because of the upward tick in each probe. I use ESV for alk and Calc. It’s a small nightly dose but it keeps my my alk around 8.3 and my ph slightly above 8 on average.

 

[SteveDola]

I dont agree in regards to not being concerned with low PH if you're keeping SPS. Ph is a determining factor on the growth rates of SPS.

 

[Swordsman82]

I run two separate cheapo ph probes. They consistently show about 0.15 apart from each other, rain or shine. What they’re good at is showing trends. You can tell exactly when I dose at night because of the upward tick in each probe. I use ESV for alk and Calc. It’s a small nightly dose but it keeps my my alk around 8.3 and my ph slightly above 8 on average.

When you say a small amount, what ratio are you doing in comparison to your tank? Your numbers are kind of the goal I would like to achieve.

 

[dz6t]

What I mean is in this case, the pH is in acceptable level. Also, sea water is a big buffer. It is very difficult to drop below 7.8 if alkalinity is in range.
There are many research has been done on pH with coral growth, especially on SPS.

In order to impact SPS growth, researchers had to lower the pH below 7.6 even to 7.2 by adding hydrochloride acid.

Chasing pH will only give you about 5 to 10% difference provided other factors are the same.

Only exception is Millipora, one study showed that it benefits from pH at above 8.2.

 

[Kens Bees]

When you say a small amount, what ratio are you doing in comparison to your tank? Your numbers are kind of the goal I would like to achieve.

About 150 gallons total. 36ml of alk and 30ml of cal starting at 11:00 each night. The averages for the last week are 8.18 alk, 410 Calc, 8.04 ph. I’d like to see higher cal but it’s so steady I don’t want to play around with it.