Neptune Aquatics

Co2 scrubber overated?

BRS brand media. I only started 3 days ago, and looking at it just now, no change in color yet. I’ll remember to add a teaspoon of water a week. I added it during initial setup.
I'm also using the BRS brand media. I do have JorVet media as well so maybe I'll switch and see if that is the issue.

Did you measure your CO2 in the room? I believe you have a well-insulated house. What is your alk? This skimmer deserves its official CO2 reactor though :). As you know, I love this setup. Any bacteria dosing, or high nutrients? Any recent ICP results?
When I borrowed the meter it was around 650ppm. Alk at 8.5, Nitrate at 8, phosphate at 0.15, no bacteria dosing and ICP results came back mostly in normal range. I do love me some Octo products but unfortunately I didn't have space in the stand for the Octo one that sits on the ground. The Icecap one hangs on the sump rim so made more logistical sense.
 
Bought a BRS co2 scrubber when it went on sale on the 4th July week. Installed it over the past weekend.

I assumed I have co2 issue thus the scrubber. Well, the results is pretty unimpressive. Maybe 0.1ph rise at most. Ph went from 7.9x to 8.0x

I read it’s more efficient when you have a close loop. Too lazy to try that especially it involved modifying the skimmer cup.

Maybe my skimmer is way too small ( tunze 9004dc) to make a different.

If I don’t have co2 issue , what could be causing low ph?

I am already dosing kalk at night. My daytime and nighttime ph is about the same.

PH is *always* a CO2 issue. Remember PH is a mathematical output of Alk and Co2 - so unless your alk is crazy low, the issue is with CO2 (could be co2 produced inside the tank or in the air outside the tank).

For those of you not seeing much impact from a CO2 scrubber, do you have a lot of surface agitation elsewhere in the tank? This surface agitation could be working hard to equalize with the CO2 in the air and be "outcompeting" the more oxygen rich air your skimmer is working to add back in. It's for this reason that CO2 scrubbers seem really inefficient and unappealing to me.

Like @Turkeysammich already said - the best thing you can do is open a window. :)
 
PH is *always* a CO2 issue. Remember PH is a mathematical output of Alk and Co2 - so unless your alk is crazy low, the issue is with CO2 (could be co2 produced inside the tank or in the air outside the tank).

For those of you not seeing much impact from a CO2 scrubber, do you have a lot of surface agitation elsewhere in the tank? This surface agitation could be working hard to equalize with the CO2 in the air and be "outcompeting" the more oxygen rich air your skimmer is working to add back in. It's for this reason that CO2 scrubbers seem really inefficient and unappealing to me.

Like @Turkeysammich already said - the best thing you can do is open a window. :)

I have 2 1000gph pump (2000gph running at 50%) pointing at the surface + 600gph return. 2 other 2000gph full speed at the bottom. Plenty of surface agitation i think. House is fully ventilated in the evening and night. I turn on the whole house fan to suck fresh in into the house then to the attic. Window close in the daytime.
 
PH is *always* a CO2 issue. Remember PH is a mathematical output of Alk and Co2 - so unless your alk is crazy low, the issue is with CO2 (could be co2 produced inside the tank or in the air outside the tank).

For those of you not seeing much impact from a CO2 scrubber, do you have a lot of surface agitation elsewhere in the tank? This surface agitation could be working hard to equalize with the CO2 in the air and be "outcompeting" the more oxygen rich air your skimmer is working to add back in. It's for this reason that CO2 scrubbers seem really inefficient and unappealing to me.

Like @Turkeysammich already said - the best thing you can do is open a window. :)

How low is low?
Unfortunately after the trident was ko’ed next went the doser decided to malfunction (realized this after I attempted calibration and was leaving on vacation).

Just had the trident replaced and it came up with alk of 5.5. Fortunately if I simply add increased dosage it is increasing the alk-back up to 6.2 now. Doing it slowly and hopefully back up to 7.8-8 by Friday.

I’ll have to contend with doser when I return.

Surprisingly the low alk/ph didn’t have as much impact as the heat.
 
How low is low?
Unfortunately after the trident was ko’ed next went the doser decided to malfunction (realized this after I attempted calibration and was leaving on vacation).

Just had the trident replaced and it came up with alk of 5.5. Fortunately if I simply add increased dosage it is increasing the alk-back up to 6.2 now. Doing it slowly and hopefully back up to 7.8-8 by Friday.

I’ll have to contend with doser when I return.

Surprisingly the low alk/ph didn’t have as much impact as the heat.

Alk has to be pretty low, but here's the table: https://docs.google.com/spreadsheet...6ii2mG4uHs/edit?gid=1100761457#gid=1100761457

Use the 2nd tab (you can find more info on this with a search - RHF covers it in a couple different articles). But the chart only goes as low as 6.5 alk. Human cognition starts to get impacted at co2 levels as low as 1000 (and it's very easy to hit 1000 in a sealed room with a couple adults). Natural air is around 300-400. So at 6.5alk with fully saturated fresh air you'll be at 8.1-8.2 PH. Assuming your tank has fully equalized with the air in the room, which does take quite a bit of time in reality.

At 1000 CO2 and 6.5 alk your PH would fall to about 7.8. I guess even lower at 5.5 alk...

edit - https://www.reefkeeping.com/issues/2004-09/rhf/
 
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I think the table is a good indication to understand the relationship of these key factors in a perfect environment, but if it was that easy to apply practically in a reef tank, people would not have low PH issues. Opening the window is great, just not when it is 90+ or below 60. Also, with 4 people in my house, I quickly get to 800 to 900 ppm again after airing the house for 30 minutes or more at which point CO2 is at around 420 ppm (the lowest value inside). This is where the CO2 scrubber comes into play. It does provide a balance from the surface agitation which pulls in high CO2 (potentially) and the low CO2 from the scrubbed air. I do not worry about PH anymore, which makes it worth it for me - still do not forget to keep CO2 low(er) in the house :).
 
Alk has to be pretty low, but here's the table: https://docs.google.com/spreadsheet...6ii2mG4uHs/edit?gid=1100761457#gid=1100761457

Use the 2nd tab (you can find more info on this with a search - RHF covers it in a couple different articles). But the chart only goes as low as 6.5 alk. Human cognition starts to get impacted at co2 levels as low as 1000 (and it's very easy to hit 1000 in a sealed room with a couple adults). Natural air is around 300-400. So at 6.5alk with fully saturated fresh air you'll be at 8.1-8.2 PH. Assuming your tank has fully equalized with the air in the room, which does take quite a bit of time in reality.

At 1000 CO2 and 6.5 alk your PH would fall to about 7.8. I guess even lower at 5.5 alk...

edit - https://www.reefkeeping.com/issues/2004-09/rhf/


Interesting indeed. Thanks. Yea it was pretty low. Managed a bypass by leaving the light in sump on 24/7 given all the current algae (attempting to regrow microalgae). Might as well as use it for something!

Prob not the best idea but better than a PH of 7.4-7.6 vs 7.8-8.0. Will contend with everything when I get home from vacation.
 
Folks that run outside air for the skimmer. Do you run the line through a window ie open a small crack ? Drill a hole on the wall? How to get a line to the outside?
 
Folks that run outside air for the skimmer. Do you run the line through a window ie open a small crack ? Drill a hole on the wall? How to get a line to the outside?
Mine I drilled a hole and used the those gaskets you use for cable TV. I used a little bit of flextape on the tubing to increase the size enough to allow the gasket to seal on the tubing.
 
Drill a hole in the wall?
correct.

This is what I used:


and some of this:

 
Also good to make sure that the end of the tube doesn't run outside next to something where a car could be idling or where pesticides are sprayed etc.

I should have mentioned that. I had a workaround... I had an old MAG canister filter chamber that I filled with carbon, and covered with filter floss. I ran the tubing into that filter.

I wasn't worried about cars, but I was worried about dirt for sure. I doubt the carbon did much after a bit outside like that, but hey, gotta try :)
 
Sorry to revive this, but I wanted to ask: what's a realistic way to reduce CO2 in the home? I don't have a trident, but I wouldn't be surprised if my pH was a flat line at 7.8, or even pH elevated at night: I can only open the window during nighttime otherwise it gets hot, meaning daytime the home (and tank) is brimming with CO2 - and this is going to flip in the winter. I imagine this is less than ideal for both the tank inhabitants and probably me.

Any ideas other than run AC aggressively?
 
Getting the CO2 meter but also do you have a PH meter of some sort? I think it’s imperative to know that- also there are other circumstances that can knock down PH -such as carbon dosing.
I have the liquid pH test from the API "saltwater test kit", but I'm really unconvinced of its accuracy. I don't really test pH because I don't trust the accuracy of the kit - and my alkalinity's at 10, so pH can't be THAT low (I hope)
 
Sorry to revive this, but I wanted to ask: what's a realistic way to reduce CO2 in the home? I don't have a trident, but I wouldn't be surprised if my pH was a flat line at 7.8, or even pH elevated at night: I can only open the window during nighttime otherwise it gets hot, meaning daytime the home (and tank) is brimming with CO2 - and this is going to flip in the winter. I imagine this is less than ideal for both the tank inhabitants and probably me.

Any ideas other than run AC aggressively?
With all that macroalgae in your tank it's probably not as low as you think haha
 
Just retested pH: lights OFF, skimmer ON, bubbler ON (Bubbler is rarely on, I use it to break up surface scum)

pH sits just below 8.0 according to the API test.
 
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