A Tale of High Indoor CO2 and Declining pH
- Thread starter cybermeez
- Start date
- Location
- Upper East Side of NYC
Just put my scubber online. Solid air seals in all the plumbing from the scrubber to the skimmer venturi. The only thing I didn't do was run a long line from the input side of the scrubber out of the stand to draw in more room air. Not sure how much a difference that would make anyway.
On the bright side - my skimmer is quieter now.
pH 7.85 when it started up. Fingers crossed. I bottomed out at 7.74 over night and that's with the fuge getting blasted with light.
On the bright side - my skimmer is quieter now.
pH 7.85 when it started up. Fingers crossed. I bottomed out at 7.74 over night and that's with the fuge getting blasted with light.
- Location
- Nutley, NJ
I have the same problem, and decided to run an experiment of my own. A few days ago I decided to build a different type of CO2 scrubber. I built the scrubber out of 2in pvc with one inlet and one outlet. The inlet has air being pushed through it by an airpump. I reconfigured the airpump so it draws air in from outside and pushes it through the scrubber. The scrubber is attached to the airline on my skimmer.
The reason I decided on this was because I have such a small skimmer I was having bad luck with the skimmer creating enough suction to draw air through the scrubber.
The air pump can be regulated so not too much air is pushed into the skimmer to alter the performance of it.
My results have been good so far and I'm quite happy. If you look at the graph, my pH is rising, but very slowly, which is what I wanted. Because the air is being pumped in, the pump could then be attached to my apex so have even more control over the pH, mostly if it were to get too high.
I also ordered a new type of pump that I'm going to try out and see if I can build this thing in a better fashion. Right now its a bit contrived, but I'm happy so far.
The reason I decided on this was because I have such a small skimmer I was having bad luck with the skimmer creating enough suction to draw air through the scrubber.
The air pump can be regulated so not too much air is pushed into the skimmer to alter the performance of it.
My results have been good so far and I'm quite happy. If you look at the graph, my pH is rising, but very slowly, which is what I wanted. Because the air is being pumped in, the pump could then be attached to my apex so have even more control over the pH, mostly if it were to get too high.
I also ordered a new type of pump that I'm going to try out and see if I can build this thing in a better fashion. Right now its a bit contrived, but I'm happy so far.
Attachments
- Location
- Deer Park,Long Island,11729
It got up to 8.17 yesterday yay
- Location
- Hudson Yards
Over the weekend the CO2 scrubber didn't seem to have any impact on the pH. I had to continue manually dosing kalkwasser. The kalk stirrer arrived today and I finished setting it up about an hour ago. It appears to have solved the problem. The pH started out at 8.10 and is now approaching 8.25.
The dosing pump feeding the stirrer is being controlled by my apex. The program is set so the pump turns on if the pH drops below 8.2 and shuts off when it gets to 8.25. It leaves some margin for error while still mitigating the pH swings the tank has been going through the past couple of weeks. I'm sure my corals and everyone else in the tank will be much happier.
What remains to be seen is just how much kalkwasser the tank will go through each day. My hope is that it won't be more than the evaporation rate and present water volume issues. I'll leave it hooked up overnight since it's when the tank experiences its lowest pH levels each 24 hour period. That should give me a better idea of what I'll be dealing with.
The dosing pump feeding the stirrer is being controlled by my apex. The program is set so the pump turns on if the pH drops below 8.2 and shuts off when it gets to 8.25. It leaves some margin for error while still mitigating the pH swings the tank has been going through the past couple of weeks. I'm sure my corals and everyone else in the tank will be much happier.
What remains to be seen is just how much kalkwasser the tank will go through each day. My hope is that it won't be more than the evaporation rate and present water volume issues. I'll leave it hooked up overnight since it's when the tank experiences its lowest pH levels each 24 hour period. That should give me a better idea of what I'll be dealing with.
Last edited:
- Location
- Hudson Yards
So far so good. Last night I left the windows cracked and the tank went through about 3/4 of a gallon of kalk solution to keep the pH between 8.2 and 8.25.
I filled up the RO reservoir before leaving for work this morning. When I got home about 9 hours later it was still a little more than 1/2 full. I think as long as there's a fan blowing across the water's surface and I keep an eye on the water level in the sump I think things will be OK.
One thing I'm still wondering about is how things might change seasonally. In the winter I don't usually have to run a fan to keep the tank cool and obviously the windows remain closed. Can those of you who are using kalk to keep your pH up tell me how things go in your tank throughout the year and if the kalk demands change?
I filled up the RO reservoir before leaving for work this morning. When I got home about 9 hours later it was still a little more than 1/2 full. I think as long as there's a fan blowing across the water's surface and I keep an eye on the water level in the sump I think things will be OK.
One thing I'm still wondering about is how things might change seasonally. In the winter I don't usually have to run a fan to keep the tank cool and obviously the windows remain closed. Can those of you who are using kalk to keep your pH up tell me how things go in your tank throughout the year and if the kalk demands change?
- Location
- Upper East Side of NYC
Interesting stuff.
I've noticed a small increase in pH since my scrubber has been online. Basically the lows are higher and the highs are higher. By higher I mean... maybe .05 to .1 I'm still not able to creep over 8 at all though. That all being said, my skimmer doesn't draw a lot of air (in terms of what's needed for my tank gallonage) and needs to be upgraded anyway for my tank size, so I'm not paying too much attention to it ... yet. New skimmer comes online in the next 72 hours, so that's when the real testing starts in regards with the scrubber.
Regarding Kalkwasser...
I tried it in my ATO reservoir too and had an impossible time keeping my alk/ca constant. I wound up with alk swings that I know were ticking off my SPS. So I abandoned that plan simply because of the unpredictable-ness of evaporation. As you said, in winter evaporation will be different so... there's that confusion.
The thing I've been toying with is simply auto-dosing kalkwasser, completely separate from the ATO. (keep the ATO as is with completely pure water) Come up with some sort of schedule and go from there. It would replace or at least reduce the need for dosing 2-part. So there's that. Figure out what you need and just program your doser to dose that amount per day. You have to make sure the kalkwasser solution is made consistently the same strength of course. With the stirrer you are already ahead of that game.
Take all this with a grain of salt, I don't have a ton of experience with kalk.
I've noticed a small increase in pH since my scrubber has been online. Basically the lows are higher and the highs are higher. By higher I mean... maybe .05 to .1 I'm still not able to creep over 8 at all though. That all being said, my skimmer doesn't draw a lot of air (in terms of what's needed for my tank gallonage) and needs to be upgraded anyway for my tank size, so I'm not paying too much attention to it ... yet. New skimmer comes online in the next 72 hours, so that's when the real testing starts in regards with the scrubber.
Regarding Kalkwasser...
I tried it in my ATO reservoir too and had an impossible time keeping my alk/ca constant. I wound up with alk swings that I know were ticking off my SPS. So I abandoned that plan simply because of the unpredictable-ness of evaporation. As you said, in winter evaporation will be different so... there's that confusion.
The thing I've been toying with is simply auto-dosing kalkwasser, completely separate from the ATO. (keep the ATO as is with completely pure water) Come up with some sort of schedule and go from there. It would replace or at least reduce the need for dosing 2-part. So there's that. Figure out what you need and just program your doser to dose that amount per day. You have to make sure the kalkwasser solution is made consistently the same strength of course. With the stirrer you are already ahead of that game.
Take all this with a grain of salt, I don't have a ton of experience with kalk.
- Location
- Deer Park,Long Island,11729
Cybermeez I'm curious what your Alk & Ca are at?
Jedi that's what I'm doing now.
KAlk DOSING
I go threw a little more that a gal a day of top off but instead
of adding Kalk to my ATO I use a doser.
There are 3785.411 mil in a Gallon
BRS 50 mil per minute doser
Dosing for 30 sec every 10 minutes
"Apex Statement"
off on off
000 / 00:30/09:30
=25mil
=150 mil per hour
=3600 mil per 24 hour(1day)
Jedi that's what I'm doing now.
KAlk DOSING
I go threw a little more that a gal a day of top off but instead
of adding Kalk to my ATO I use a doser.
There are 3785.411 mil in a Gallon
BRS 50 mil per minute doser
Dosing for 30 sec every 10 minutes
"Apex Statement"
off on off
000 / 00:30/09:30
=25mil
=150 mil per hour
=3600 mil per 24 hour(1day)
A little bit of an update on my side.
I noticed that the cable installer had left a hole going through the wall to the outside, and I was able to attach a 40 foot long air line to it without any major issues (no kinking on the line).
I have tried the three-way solenoid that I was mentioning before, the problem is that it runs crazily hot. To the point where you would burn yourself if you touch it. Since it is overkill in terms of spec for that application (my skimmer does not draw 120PSI
), I am trying to find a "low-wattage" version that should run cooler.
Without the scrubber and just by getting outside air as mentioned before, I am now at 8.22 - 8.40. With a KH of 7.7.
I noticed that the cable installer had left a hole going through the wall to the outside, and I was able to attach a 40 foot long air line to it without any major issues (no kinking on the line).
I have tried the three-way solenoid that I was mentioning before, the problem is that it runs crazily hot. To the point where you would burn yourself if you touch it. Since it is overkill in terms of spec for that application (my skimmer does not draw 120PSI
), I am trying to find a "low-wattage" version that should run cooler.Without the scrubber and just by getting outside air as mentioned before, I am now at 8.22 - 8.40. With a KH of 7.7.
- Location
- Nutley, NJ
I'm working with the same issue. I ordered a special air pump and a vacuum gauge to run some tests to see how much volume I can pull.
Are you using 1/4 or 3/8 tubing?
Are you using 1/4 or 3/8 tubing?
- Location
- Deer Park,Long Island,11729
I'm using 3/8
- Location
- Upper East Side of NYC
Hey Mike, do you dose 2-part as well, or does all that kalkwasser cover your Ca and Alk needs? I burn through a lot of both so I"m curious as we have the same size tank, gallonage wise (mine is long - 60", and I have sand, but close enough) and you seem to have the same SPS addiction I have
- Location
- Deer Park,Long Island,11729
Hey Mike, do you dose 2-part as well, or does all that kalkwasser cover your Ca and Alk needs? I burn through a lot of both so I"m curious as we have the same size tank, gallonage wise (mine is long - 60", and I have sand, but close enough) and you seem to have the same SPS addiction I have
NO I stopped the two part when I went with Kalk and its maintaining
Ca 450
Alk 9.5-10 DKH
- Location
- Hudson Yards
I haven't measured the Ca and Alk since bringing the Kalk stirrer online, but I planned to do it tonight after work since I did a water change last night (with Reef Crystals) and that tends to cause everything except Mg to drop. I'll post them tonight as soon as I have them.
I last tested 4 days ago when the scrubber was up and running, but I was still manually dosing kalk. My Ca was 490, Alk was 12.9 and Mg was 1440.
Before that my test results on 8/4 were Ca 510, Alk 14 and Mg 1320.
I periodically dose Mg since my calcium is running so high, otherwise it would probably precipitate out pretty rapidly.
- Location
- Hudson Yards
Here are this evening's tank parameters:
Ca=490
Alk=11.9
Mg=1240
PO4=0.2
NO3=0
I hate the stuff, but I pulled some grape caulurpa from my nano tank and tossed it into the sump. I prefer chaeto, but I can't get it to grow in my sump. The caulurpa on the other hand grows like a weed. I've also put the sump on a reverse lighting schedule so it's on at night when the main tank lights are off.
I want to get the tank stable again so I can replace the corals I lost.
Ca=490
Alk=11.9
Mg=1240
PO4=0.2
NO3=0
I hate the stuff, but I pulled some grape caulurpa from my nano tank and tossed it into the sump. I prefer chaeto, but I can't get it to grow in my sump. The caulurpa on the other hand grows like a weed. I've also put the sump on a reverse lighting schedule so it's on at night when the main tank lights are off.
I want to get the tank stable again so I can replace the corals I lost.
- Location
- Nutley, NJ
Here's a little update with my experiment. I purchased a vacuum/pressure gauge. Took readings on the intake line on the skimmer and came up with 38.1mm Hg. When I hook the gauge up to the line that is running from the pump outside, I come up with 50.8mm Hg while running the air pump at full. Prior to this, I was running the pump at a bit less than half so as not to pump too much air into the skimmer. I put a small airline regulator on the line going into the CO2 scrubber to optimize the pressure.
I'll be curious to see how this works out.
On the other end of things, I ordered a new form of air pump that actually has a vacuum intake on it. I'll be curious to see if this new pump has more suction, and hopefully is a bit quieter.
So far I'm quite happy with my results. More to come...
I'll be curious to see how this works out.
On the other end of things, I ordered a new form of air pump that actually has a vacuum intake on it. I'll be curious to see if this new pump has more suction, and hopefully is a bit quieter.
So far I'm quite happy with my results. More to come...
- Location
- Hudson Yards
Djbetterly, can you post a photo of your scrubber set up?
The kalk stirrer has been going for several days and I may have traded one problem for another. The tank's kalk requirements to keep the Co2 in check means more kalk solution is going into the tank than the amount of water being lost to evaporation. This is driving the salinity down. Over the the course of a few days it went from 1.026 to 1.024.
This morning I added some highly saturated salt solution to correct the salinity decline and some Seachem Marine Buffer to bring the pH up a little. Though in my experience the buffer's changes won't last more than a day.
I'm at a bit of a loss as what try next. My skimmer can't pull anymore air through the scrubber. The only other thing I can think of it to figure out a way to pull fresh air in from outside, push it through a carbon filter to remove pollutants, then through the soda lime to scrub Co2 and into the tank via an air stone in the sump. And even then there's no guarantee it's going to work. But if I can influence the pH just enough to reduce the amount of kalk solution going into the tank that little bit may be all I need.
To do this the pump is going to have to be pretty strong because the air has to travel approximately 15 feet and make it through the resistance of the media before going to the tank. Any suggestions?
The kalk stirrer has been going for several days and I may have traded one problem for another. The tank's kalk requirements to keep the Co2 in check means more kalk solution is going into the tank than the amount of water being lost to evaporation. This is driving the salinity down. Over the the course of a few days it went from 1.026 to 1.024.
This morning I added some highly saturated salt solution to correct the salinity decline and some Seachem Marine Buffer to bring the pH up a little. Though in my experience the buffer's changes won't last more than a day.
I'm at a bit of a loss as what try next. My skimmer can't pull anymore air through the scrubber. The only other thing I can think of it to figure out a way to pull fresh air in from outside, push it through a carbon filter to remove pollutants, then through the soda lime to scrub Co2 and into the tank via an air stone in the sump. And even then there's no guarantee it's going to work. But if I can influence the pH just enough to reduce the amount of kalk solution going into the tank that little bit may be all I need.
To do this the pump is going to have to be pretty strong because the air has to travel approximately 15 feet and make it through the resistance of the media before going to the tank. Any suggestions?
- Location
- Nutley, NJ
- Location
- Hudson Yards
What air pump can I use that will have an inlet when I can run a line into it from outside and an outlet where I can run a line to the tank?
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