CO2 scrubber worth it in this case?

[BAMatter]

With a scrubber, my system holds 8.3 with kalk dosing PH based, and rises significantly during the day. I have a solenoid that opens at 8.32 to bypass the scrubber media to extend life. With the media exhausted, around 10/9, my PH at night dips to 8.24-8.25 (kalk doses every 17 mins PH based so essentially doses regardless) and gets as high as 8.33 during the day. So, that said- couple questions come up-

1) am I splitting hairs by using the scrubber or is the $120 of media every 6-7 months worth it given the chart below?

2) if I pull the scrubber, should I lower the kalk dose PH parameter so it holds a PH bottom line as opposed to just dosing an amount over night (still less than evap rate currently)

3) am I overthinking this like I do everything else and just let it rip? I did need to lower my 2 part since the extra kalk had bumped my alk up for the past couple tests and I didn’t want it getting too high.

 

[Garf]

With a scrubber, my system holds 8.3 with kalk dosing PH based, and rises significantly during the day. I have a solenoid that opens at 8.32 to bypass the scrubber media to extend life. With the media exhausted, around 10/9, my PH at night dips to 8.24-8.25 (kalk doses every 17 mins PH based so essentially doses regardless) and gets as high as 8.33 during the day. So, that said- couple questions come up-

1) am I splitting hairs by using the scrubber or is the $120 of media every 6-7 months worth it given the chart below?

2) if I pull the scrubber, should I lower the kalk dose PH parameter so it holds a PH bottom line as opposed to just dosing an amount over night (still less than evap rate currently)

3) am I overthinking this like I do everything else and just let it rip? I did need to lower my 2 part since the extra kalk had bumped my alk up for the past couple tests and I didn’t want it getting too high.

I get bad vibes thinking about dosing Kalk dependant upon pH probes to be honest. You not considered just dosing a set amount to maintain Alk? Then reassess.

 

[BAMatter]

I get bad vibes thinking about dosing Kalk dependant upon pH probes to be honest. You not considered just dosing a set amount to maintain Alk? Then reassess.

That’s pretty much what’s happening at this point since kalk is being dosed per the schedule and not turning off due to the lower PH. Really almost wish I never got a controller with a PH probe. All this data is driving me crazy and making me tinker.

 

[jda]

I would not worry about that pH. If indoor air is a problem, then just air out as much as you can, when you can, and let the rest ride.

I also do not trust a pH probe with anything. Always the weakest link in any setup. I am glad that you are not doing this.

Sometimes the best thing to do is to get an indoor co2 monitor and keep the house/room co2 under 600 ppm, but closer to 400 the better. This nearly always has good pH even without kalk. They are about $50 on amazon. We take ours on vacation so that we are not sleeping in a 2000ppm co2 hotel or airbnb, which has happened.

 

[BAMatter]

I would not worry about that pH. If indoor air is a problem, then just air out as much as you can, when you can, and let the rest ride.

I also do not trust a pH probe with anything. Always the weakest link in any setup. I am glad that you are not doing this.

Sometimes the best thing to do is to get an indoor co2 monitor and keep the house/room co2 under 600 ppm, but closer to 400 the better. This nearly always has good pH even without kalk. They are about $50 on amazon. We take ours on vacation so that we are not sleeping in a 2000ppm co2 hotel or airbnb, which has happened.

Well I have been dosing PH based. The amount dosed varies by maybe 200ml +/- during the lights off period, which doesn’t do much in terms of alk, but did keep PH above 8.29. I’m likely going to go back to my Kamoer and drip 4ml/min from 10:00pm thru 11:00am the next day and call it a day. Really have had inconsistent probe experiences with calibration, drifting, etc…

 

[Randy Holmes-Farley]

Well I have been dosing PH based. The amount dosed varies by maybe 200ml +/- during the lights off period, which doesn’t do much in terms of alk, but did keep PH above 8.29. I’m likely going to go back to my Kamoer and drip 4ml/min from 10:00pm thru 11:00am the next day and call it a day. Really have had inconsistent probe experiences with calibration, drifting, etc…

Just realize that if you pull the scrubber, alk may get higher than you want before hitting your pH target.

 

[BAMatter]

Just realize that if you pull the scrubber, alk may get higher than you want before hitting your pH target.

Due to the extra kalk being dosed?

 

[Randy Holmes-Farley]

Due to the extra kalk being dosed?

Yes, because it will take more kalk to get to the pH target.

 

[BAMatter]

Yes, because it will take more kalk to get to the pH target.

The PH chart above shows the decrease without using the scrubber. It’s not a substantial amount more of Kalk that it dosed. Maybe a few hundred ml’s for an 85 gallon ish system. That being said, the amount of kalk I’m putting in is my evap rate and it can’t keep 8.3 at lights off cycle, and it’s dipping to 8.24-8.25 area. Is that extra bump in PH worth it to keep the scrubber online?

 

[Someshmuk]

I wouldn't trust ph probes highs/lows as they are not indicative of the actual ph reading on the tank. We're using hobbyist equipment unfortunately. What i would look out for is rapid +/- 0.2 rate changes as that would indicate something horrible has happened.

But... If you're feeling real spicy and you have access to a programmable doser, you can dose small amounts of sodium hydroxide (12-14) into your tank to manage your alkalinity. ph gain is significant vs sodium carbonate (10-11). But also, it's significantly more dangerous, (can burn you real bad, kill your tank on the wrong dose). Keep in mind, CO2 scrubbers are sodium hydroxide crystals empregnated with an indicator to make it go pink when its been converted to sodium bicarbonate or carbonate.

 

[Randy Holmes-Farley]

The PH chart above shows the decrease without using the scrubber. It’s not a substantial amount more of Kalk that it dosed. Maybe a few hundred ml’s for an 85 gallon ish system. That being said, the amount of kalk I’m putting in is my evap rate and it can’t keep 8.3 at lights off cycle, and it’s dipping to 8.24-8.25 area. Is that extra bump in PH worth it to keep the scrubber online?

Ok, I was addressing the idea of dosing based on pH, which would cause an alk rise to maintain pH. If you are not controlling by pH, then removing the scrubber may cause pH and alk demand to drop, and alk may still rise a bit.

Whether it is worth it is a question only you can answer based on your goals.

 

[Randy Holmes-Farley]

I wouldn't trust ph probes highs/lows as they are not indicative of the actual ph reading on the tank. We're using hobbyist equipment unfortunately. What i would look out for is rapid +/- 0.2 rate changes as that would indicate something horrible has happened.

But... If you're feeling real spicy and you have access to a programmable doser, you can dose small amounts of sodium hydroxide (12-14) into your tank to manage your alkalinity. ph gain is significant vs sodium carbonate (10-11). But also, it's significantly more dangerous, (can burn you real bad, kill your tank on the wrong dose). Keep in mind, CO2 scrubbers are sodium hydroxide crystals empregnated with an indicator to make it go pink when its been converted to sodium bicarbonate or carbonate.

Scrubbers are not typically sodium hydroxide, but soda lime.

 

[Someshmuk]

Scrubbers are not typically sodium hydroxide, but soda lime.

Ew, that sounds even worse than what i initially thought. I'm looking at that now and it looks like an composition of calcium oxide, sodium hydroxide, water, and potassium hydroxide. I feel like it'd be a cheaper option to use sodium hydroxide as your alk supplment/ph buffer.

 

[BAMatter]

Ew, that sounds even worse than what i initially thought. I'm looking at that now and it looks like a composition of calcium oxide, sodium hydroxide, water, and potassium hydroxide. I feel like it'd be a cheaper option to use sodium hydroxide as your alk supplment/ph buffer.

You do know we’re talking about a CO2 scrubber right? Not an alk supplement.

 

[YOYOYOReefer]

Ew, that sounds even worse than what i initially thought. I'm looking at that now and it looks like a composition of calcium oxide, sodium hydroxide, water, and potassium hydroxide. I feel like it'd be a cheaper option to use sodium hydroxide as your alk supplment/ph buffer.

Seriously how could you think it was just sodium hydroxide is sole chemical used in a scrubber bead? it would go into solution with water . You shoululd not be giving advice on this topic.

to the op if you remove the scrubber your ph will go down not up, Recommend running your skimmer air line to outside

 

[BAMatter]

Seriously how could you think it was just sodium hydroxide is sole chemical used in a scrubber bead? it would go into solution with water . You shoululd not be giving advice on this topic.

to the op if you remove the scrubber your ph will go down not up, Recommend running your skimmer air line to outside

I’m aware it will go down… I’m weighing out of the .05 gain in PH is worth it or not to be using scrubber media

 

[YOYOYOReefer]

I don’t think the scrubber media is needed in your case . you seem to understand the chemistry very well.

 

[BAMatter]

I don’t think the scrubber media is needed in your case . you seem to understand the chemistry very well.

My PH is low in this system. I need to jam evap rate to hold 8.3 during lights off cycle. My scrubber air path flips on and off with a solenoid depending on PH set point. It does drop.

 

[YOYOYOReefer]

Why do you think need to hold ph 8.3.

 

[BAMatter]

Why do you think need to hold ph 8.3.

Because I’m a brainwashed member of the reefers utopia