Question for those that have a basement system. CO2!!!

[Want2BS8ed]

Does it matter where you put the solenoid, on the fresh air line or the skimmer line?

Not really, for safety's sake I would place it higher than the skimmer. I placed mine on top of the skimmer out of convenience...

Let us know how it goes!

M

PS been sitting in the DMV for an hour already... fire away with any questions - there is only so much surfing and solitaire one can play!!!

 

[jessezm]

Jumping back in I hope you don't mind... So I just fed my CO2 scrubber from the skimmer cup to the second air intake in my Reef Octo Regal 250 sss. Mind you, the cup has multiple holes for venting and I just stuck a tube in one of them. The other air intake for the skimmer (it has two) is coming from a line fed to the outside (my system is basement as well). I don't have a solenoid hooked up but I figured feeding it from the outside to the skimmer and from the skimmer cup to the CO2 scrubber would be safe. I know the CO2 scrubber is drawing air from the skimmer cup (though doesn't feel like as much as it's drawing from the outside), because I can feel the suction, and also because the inside of the CO2 scrubber is now foggy/moist looking. However, I've noticed no apparent difference in pH since making the change last night.

Is it possible that there is so much surface agitation in the tank that the CO2 inside the basement is limiting/negating any effect from air coming from the outside to the skimmer or from the CO2 scrubber? I do know for a fact that if I shut my skimmer off or feed it from inside, the pH drops immediately in the tank.

The system is 100 total gallons currently, being fed Kalkwasser from the ATO reservoir (goes through about 6/gal per week) with the addition of a Korralin calcium reactor being fed a stead stream with pH pegged at 6.8 - 6.9

pH in my tank fluctuates from 7.9 at night to 8.1 during the day (pH probe new and calibrated 3 times). Not terrible numbers, but I feel they could be better. Also, I struggle to maintain ALK at 7 dKh. Coralline algae is growing like crazy and I have a good amount of SPS (acros and montis) that seem to be growing fairly well, which is probably why I struggle to keep the Alk up.

Other measures include a reverse light cycle Chaeto refugium in the sump.

Should I try just feeding the CO2 scrubber dry air from the outside (well it's humid here in Atlanta), and then directly to the skimmer, and plugging the other hole to see if it makes any difference? I liked the idea posed above of feeding it humid skimmer-cup air in order to help preserve the media for longer, but that may not be working...

 

[Randy Holmes-Farley]

Is it possible that there is so much surface agitation in the tank that the CO2 inside the basement is limiting/negating any effect from air coming from the outside to the skimmer or from the CO2 scrubber? I do know for a fact that if I shut my skimmer off or feed it from inside, the pH drops immediately in the tank.
.

Tank top aeration does fight the CO2 removal from skimmer air if the air in the room has a lot of CO2. Some people find the skimmer method not completely effective, and this is the likely reason.

 

[jessezm]

Thanks Randy, any recommendations?

 

[anit77]

Fire your questions away jessezm, I've got no problem with it. The more the merrier

I ordered the Soda Lime for Ebay today, so I'm hopping to have it around the end of the week. I have an old BRS reactor laying around and I'm going to get it ready to be plumbed up in the mean time. I'm also going to start out just 100% recycling the air from the skimmer through the scrubber and see how it goes. If the pH shoots up too high I'll look into getting a solenoid. All of my air & drain lines are 1/2" and I'm having a hard time finding one that size and 24VDC for a reasonable price. The nearest energy bar I have is an 832 but all 8 are in use, so I'd like to go 24v instead. I'm going to look for a 3/8" next and see if I can find one under $50.
The sodium hydroxide will be here next week too.

 

[anit77]

7/8/18 Alk 8.18; Cal 411; pH 7.93. Adjusted Alk to 9.5 & cal to 425.
7/9/18 Alk 9.24; Cal 424; pH 8.03
7/10/18 Alk 8.85; Cal 421; pH 7.97

 

[jessezm]

You should post the time of your measurements, too ;-)
I should make a slight update to my experience as well: Yesterday was the first full day of having my CO2 scrubber on, and the pH did actually climb slightly higher, and stayed there for significantly longer than usual. The 24 hr average was .05 higher than usual (8.06 vs 8.01) Here's about 3 days for comparison:

 

[anit77]

All tests were done between 8 & 8:30pm. I'll add that to the next update.

I got the shipping info already and the Soda Lime will be delivered tomorrow.

 

[anit77]

I'm going to start a new thread about the alk consumption and keep this one on topic.

 

[Gareth elliott]

Anecdotal no ph numbers to share with this as i haven’t actually tested them since this but. After reading your thread i plumbed my skimmer to a fresh air line. Have noticed increased PE since doing so. The parameters i do test alk, ca, mg, no3 and po4 have remained stable.

Only change was the fresh air line.

Tank isnt a basement tank, but tank room does include a co2 injected planted.

Not a proven case as i dont know how much an effect this was having in the first place or if the fresh air is the cause of the PE increase.

 

[anit77]

Gareth, glad you're seeing improvement after adding a fresh air line. If I didn't have one in place my pH would be consistently under 7.85.
I think most systems could benefit from an outside air line connected to their skimmer.

I'm going to have a co2 scrubber connected to my skimmer today. It's going to be interesting to see how much of an impact ts going to have.

 

[anit77]

I got the scrubber hooked up as planned on Sunday. Fortunately I had everything I needed except a few fittings. The pH is up about 0.10 and the nightly low has't dropped under 8.0 so far.

Right now it's plumbed in a closed loop with no outside air. The skimmer is still producing a nice foam head but after reading what Randy said about the air getting stale and possibly having lower o2 I've been connecting the outside air line to the injector for a few minutes a day. I found a solenoid on ebay that will arrive on Friday and I'll plumb in a tee with the solenoid connected to the outside line. I don't have to worry about the pH getting to 8.4 anytime soon so I plan to program an osc line to open the valve a couple times a day for a few minutes to allow some fresh air in.

As I typed this I realized there was no way to vent the air out of the closed loop without another tee and solenoid connected before the scrubber... DOH
Maybe it will pull a little bit of fresh air in, I don't know.

 

[Want2BS8ed]

I got the scrubber hooked up as planned on Sunday. Fortunately I had everything I needed except a few fittings. The pH is up about 0.10 and the nightly low has't dropped under 8.0 so far.

Right now it's plumbed in a closed loop with no outside air. The skimmer is still producing a nice foam head but after reading what Randy said about the air getting stale and possibly having lower o2 I've been connecting the outside air line to the injector for a few minutes a day. I found a solenoid on ebay that will arrive on Friday and I'll plumb in a tee with the solenoid connected to the outside line. I don't have to worry about the pH getting to 8.4 anytime soon so I plan to program an osc line to open the valve a couple times a day for a few minutes to allow some fresh air in.

As I typed this I realized there was no way to vent the air out of the closed loop without another tee and solenoid connected before the scrubber... DOH
Maybe it will pull a little bit of fresh air in, I don't know.

If you read through Randy's follow-up the response was maybe... maybe not and we never really did get an answer as to what came out of the scrubber once the CO2 went in, only the end state of the media.

If you were truly running a "closed loop", stale air "might" be an issue, but you are still venting your waste collector through carbon for odor aren't you? Think of that vent as a two way street that will help maintain pressure equilibrium.

If you choose to bypass the scrubber with outside air, any excess will be vented through your waste collector as before, so no real need for a second valve.

Can you post some more details about the eBay valve? It would be nice to find a less expensive alternative to the MC valve.

 

[anit77]

Yes, I'm running a true closed loop. I got another PVC cap that sits atop the carbon chamber, drilled it and attached a barbed fitting to it. There is no air that escapes the skimate bucket. The air that runs though the scrubber is quite humid and the media looks like its doing very well.

I could connect another fitting to the lid on the bucket to alleviate the need for another solenoid. I may do that.

This is the one I got on Ebay. It's 1/2" but they have many sizes to choose from.
https://www.ebay.com/itm/290562138382

 

[Want2BS8ed]

Yes, I'm running a true closed loop. I got another PVC cap that sits atop the carbon chamber, drilled it and attached a barbed fitting to it. There is no air that escapes the skimate bucket. The air that runs though the scrubber is quite humid and the media looks like its doing very well.

I could connect another fitting to the lid on the bucket to alleviate the need for another solenoid. I may do that.

This is the one I got on Ebay. It's 1/2" but they have many sizes to choose from.
https://www.ebay.com/itm/290562138382

Nice call on the valve. SS, Viton seal; should work well. Let us know what it looks like and your thoughts when it arrives.

There is no need to run a completely closed loop. In that situation, Randy's thoughts would be valid. There needs to be some exchange as well.

 

[sawdonkey]

This may help...

Those are 3/8" lines (including the valve), which are the standard input size for the MRC Orca skimmer. Here is one of the threads as well:

My Experience Raising pH

https://r.tapatalk.com/shareLink?sh...My-Experience-Raising-pH.394826/&share_type=t

If you have more specific questions, just let me know.

M

So basically, you’re pulling already-scrubbed air into your scrubber? The scrubbed air would have just gone into the atmosphere had you not pulled it back into the scrubber? By doing this, the air going through the scrubber already has reduced CO2 and therefore you use up less media? If I understand this correctly, this is genius!

The moisture from the skimmer has nothing to do with it, right?

 

[anit77]

So basically, you’re pulling already-scrubbed air into your scrubber? The scrubbed air would have just gone into the atmosphere had you not pulled it back into the scrubber? By doing this, the air going through the scrubber already has reduced CO2 and therefore you use up less media? If I understand this correctly, this is genius!

The moisture from the skimmer has nothing to do with it, right?

If you have a closed cup skimmer, a Life Reef or MTC, then yes, you will be cycling already scrubbed air. With a normal skimmer you will be pulling some of the already scrubbed air and some ambient air to the scrubber. With both, the scrubber will be pulling co2 that the skimmer exchanged from the tank water but there is probably much less co2 than from the surrounding air.

From my understanding, it's actually that humid air that you are feeding to the scrubber from the skimmer that does the most good in extending the life of the media. Along with the lowered co2 coming out of the skimmer. Someone please correct me if I have that wrong.

 

[Want2BS8ed]

So basically, you’re pulling already-scrubbed air into your scrubber? The scrubbed air would have just gone into the atmosphere had you not pulled it back into the scrubber? By doing this, the air going through the scrubber already has reduced CO2 and therefore you use up less media? If I understand this correctly, this is genius!

The moisture from the skimmer has nothing to do with it, right?

No the humid air is the main extender of media life. That air is partially recycled to me is just a bonus. I am not running a closed system to be clear. My skimmer cup remains vented so there is some air exchange taking place.

If you have a closed cup skimmer, a Life Reef or MTC, then yes, you will be cycling already scrubbed air. With a normal skimmer you will be pulling some of the already scrubbed air and some ambient air to the scrubber. With both, the scrubber will be pulling co2 that the skimmer exchanged from the tank water but there is probably much less co2 than from the surrounding air.

From my understanding, it's actually that humid air that you are feeding to the scrubber from the skimmer that does the most good in extending the life of the media. Along with the lowered co2 coming out of the skimmer. Someone please correct me if I have that wrong.

No correction needed. Your explanation is spot on!

 

[sawdonkey]

No the humid air is the main extender of media life. That air is partially recycled to me is just a bonus. I am not running a closed system to be clear. My skimmer cup remains vented so there is some air exchange taking place.



No correction needed. Your explanation is spot on!

Ok, but why does the humid air extend the life of the media? What is happening chemically?

I’m not implying that the recycled air is the main benefit, but my logic (which isn’t always sound) would tell me that this is.

 

[anit77]

I'm no chemist...l but I think it has to do with allowing the individual pellets to absorb more co2 before a carbonate shell seals off the interior or those pellets.