Co2 Scrubber issues and proper use questions

[m.kristoff]

I am new to Scrubbers and ran across a pretty big issue.

I have a BRS scrubber using BRS media. I have a Reef Octo 200EXT skimmer. I started using the scrubber with it drawing outside air. I did see a modest PH increase to maybe 8.05 - 8.1. from was around 7.7 - 8.0 without it. I read several articles about setting it up to recirculate. I attached the intake to my skimmer cup and my PH almost immediately jumped up to a low of 8.05 at night and 8.2 during the day. That turned out to be too rapid of a change and the few small sps frags I have started to RTN. All my euphyllia are fine and looked great.

I have an Alkatronic that measures 4 times a day and my average dkh is between 9.19 to 9.4 consistently with dosing 1500ml of kalk over 24 hours. The tank was very stable.
I noticed that my DKH was creeping up and is at a high of 9.77

I also noticed a decline in my PH so I looked at the scrubber. I found that that container filled about a 1/4 with water and the media got wet. The weather in Ohio changed to the 80's and the humidity in my skimmer increased. I use the BRS media which is Soda Ash. BRS told me that it was basically pelletized Kalk. That explained why my DKH is going up and my pH was dropping. I have turned off the Kalk dosing until the DKH drops back down.

My questions are.
1. want is the optimal way to run a scrubber? outside air only or recirculate? should i consider a "pre chamber" to collect the humidity before it hits the media?
2. how do I ease my system into the higher PH so I don't have stability issues
3. with my nighttime lows of 7.7 and day time highs of 7.8 - 8.0 pH should I even bother with a scrubber?

 

[glb]

I am new to Scrubbers and ran across a pretty big issue.

I have a BRS scrubber using BRS media. I have a Reef Octo 200EXT skimmer. I started using the scrubber with it drawing outside air. I did see a modest PH increase to maybe 8.05 - 8.1. from was around 7.7 - 8.0 without it. I read several articles about setting it up to recirculate. I attached the intake to my skimmer cup and my PH almost immediately jumped up to a low of 8.05 at night and 8.2 during the day. That turned out to be too rapid of a change and the few small sps frags I have started to RTN. All my euphyllia are fine and looked great.

I have an Alkatronic that measures 4 times a day and my average dkh is between 9.19 to 9.4 consistently with dosing 1500ml of kalk over 24 hours. The tank was very stable.
I noticed that my DKH was creeping up and is at a high of 9.77

I also noticed a decline in my PH so I looked at the scrubber. I found that that container filled about a 1/4 with water and the media got wet. The weather in Ohio changed to the 80's and the humidity in my skimmer increased. I use the BRS media which is Soda Ash. BRS told me that it was basically pelletized Kalk. That explained why my DKH is going up and my pH was dropping. I have turned off the Kalk dosing until the DKH drops back down.

My questions are.
1. want is the optimal way to run a scrubber? outside air only or recirculate? should i consider a "pre chamber" to collect the humidity before it hits the media?
2. how do I ease my system into the higher PH so I don't have stability issues
3. with my nighttime lows of 7.7 and day time highs of 7.8 - 8.0 pH should I even bother with a scrubber?

1. I don’t have the option for outside air but most people recommend that first. I use BRS co2 scrubber media and an old TLF GFO reactor that’s the perfect size to run the media. I drilled a hole in the skimmer lid and put the tubing just barely in the hole. I found out the hard way that if I inserted it too far that skimmate would humidify the media and once it got wet, IME it was ineffective. I live in South Florida so I know about humidity! If I see humidity building up in the tubing I just pull it out of the skimmer lid and let it dry out.
2. If you have an apex you could set an alarm if the ph went past a certain point and disconnect the scrubber for a bit. Not a perfect solution because you’d have to be home!
3. This all depends. If your tank was doing well and was stable before adding the scrubber, you could probably do without it. I don’t have much SPS so the ph jumps when I change the media don’t bother my corals.

As far as the alk, I don’t quite understand the increase. When you raise ph, corals tend to grow faster and this in turn usually lowers the alk.

You mentioned that you were using Soda Ash, but the Co2 scrubber media is in pellet form. I’m assuming that you’re using the pellets but just wanted to make sure. Hope this helps!

 

[SPS2020]

I repurposed a BRS GFO and Carbon canister setup. The recirculation configuration comes out of the protein skimmer lid into the first canister which has one foam disc and the other contains the soda lime. The "prefilter" catches the excess moisture and keeps the soda ash dry.

 

[m.kristoff]

You mentioned that you were using Soda Ash, but the Co2 scrubber media is in pellet form. I’m assuming that you’re using the pellets but just wanted to make sure. Hope this helps!

It is pelletized soda ash.

As far as the alk, I don’t quite understand the increase. When you raise ph, corals tend to grow faster and this in turn usually lowers the alk.

all was going well until the media got wet. as I understand it, since that media is basically Kalk, it was releasing back into the system on top of the 1500ml i was already dosing. My Dkh was stable at the low to mid 9's. it jumped up to 9.7 so its not a crazy jump but enough to address it.

 

[m.kristoff]

I repurposed a BRS GFO and Carbon canister setup. The recirculation configuration comes out of the protein skimmer lid into the first canister which has one foam disc and the other contains the soda lime. The "prefilter" catches the excess moisture and keeps the soda ash dry.

I have the same canisters and was looking to do the exact same thing. how much water collects in the first chamber?

 

[SPS2020]

I have the same canisters and was looking to do the exact same thing. how much water collects in the first chamber?

Not very much, yet. I was running without the sponge initially, but some condensation did creep over into the other container. Very satisfied thus far.

 

[SPS2020]

Also, depending upon your need, Jorvet sells 5 gallon containers of Soda Lime on ebay for $104 shipped. I picked up one a few months back and it will be way cheaper than BRS.

Update: I mentioned "soda ash" in a previous post, but meant soda lime.

 

[glb]

Also, depending upon your need, Jorvet sells 5 gallon containers of Soda Lime on ebay for $104 shipped. I picked up one a few months back and it will be way cheaper than BRS.

Update: I mentioned "soda ash" in a previous post, but meant soda lime.

Oh ok. That makes sense.

 

[Bpb]

I will never understand the recommendation to recirculate the air by putting the intake in the skimmer cup. All you will do is suck in foam until your co2 scrubber turns into a skimmate locker, eventually filling up and causing the very issue you had. It’s happened to me as well. Best way to use a scrubber is to simply let it draw room air or outside air. Not recirculating. Squirt 20 ml or so of water into the bottom of the scrubber every day to keep it humid and replace the media if ph drops below 8.

 

[m.kristoff]

All you will do is suck in foam until your co2 scrubber turns into a skimmate locke

that didn't happen. The weather in Ohio changed to highs in the 80's and the humidity was higher. I originally ran it with outside air and still couldn't maintain a pH above 8 consistently. I can with it recirculating

 

[glb]

I will never understand the recommendation to recirculate the air by putting the intake in the skimmer cup. All you will do is suck in foam until your co2 scrubber turns into a skimmate locker, eventually filling up and causing the very issue you had. It’s happened to me as well. Best way to use a scrubber is to simply let it draw room air or outside air. Not recirculating. Squirt 20 ml or so of water into the bottom of the scrubber every day to keep it humid and replace the media if ph drops below 8.

If you place the intake properly, the skimmate never reaches it. You also have to clean the skimmer more often, but I’ve never had a problem. You recirculate it because the media lasts much longer this way.

 

[Bpb]

If you place the intake properly, the skimmate never reaches it. You also have to clean the skimmer more often, but I’ve never had a problem. You recirculate it because the media lasts much longer this way.

I squeegee my skimmer cups daily, they still fill with foam and the air draw is strong enough to suck it into the scrubber

 

[m.kristoff]

If you place the intake properly, the skimmate never reaches it. You also have to clean the skimmer more often, but I’ve never had a problem. You recirculate it because the media lasts much longer this way.

I have a Reef Octo 200ext. The intake is high on the cup and I use a float switch that will shut the skimmer down if the skimmate reaches just under the intake.

 

[youcallmenny1]

Position the scrubber correctly and this won't happen. Recirculating works very well if the tube between the skimmer lid and the scrubber is as vertical as possible. It should not have an S or any downward slope. If skimmate is still reaching it, the line needs to be longer or you need to turn your skimmer down a little. These simple things keep mine running perfectly. I too had these same problems and that's how I fixed them.

 

[m.kristoff]

this seems to be working. I am considering moving the scrubber higher than the skimmer. I f I do that, I should be able to eliminate the pre-chamber

 

[youcallmenny1]

this seems to be working. I am considering moving the scrubber higher than the skimmer. I f I do that, I should be able to eliminate the pre-chamber

Yes, the scrubber should 100% be positioned higher than the skimmer of you're going to recirculate it.

 

[piranhaman00]

Yes, the scrubber should 100% be positioned higher than the skimmer of you're going to recirculate it.

Mine is lower than skimmer without issue. Are you staying this for condensation issue?

I run a T with ball valve out of the skimmer cup to allow a very small amount of fresh air to be pulled in, this adequately keeps the condensation out of the chamber while bringing in moist air

 

[Bpb]

I don’t mean my scrubber pulls the liquid skimmate from the bottom of the cup. The air draw is strong enough that it sucks the foam into the tubing as it spills over the neck. Before it can even reach the bottom of the cup. Eventually the foam reduces to liquid which fills the scrubber

 

[youcallmenny1]

Mine is lower than skimmer without issue. Are you staying this for condensation issue?

I run a T with ball valve out of the skimmer cup to allow a very small amount of fresh air to be pulled in, this adequately keeps the condensation out of the chamber while bringing in moist air

No, it's getting sucked out the top of the cup. I'm glad yours isn't doing that but this is a pretty common issue. I also have a second air line run from the secondary intake to the outside of the stand with a ball valve on it. If my PH gets too high, I open that a little. Either way, it's definitely the foam getting sucked out the top on a recirc that we're complaining about.

 

[youcallmenny1]

I don’t mean my scrubber pulls the liquid skimmate from the bottom of the cup. The air draw is strong enough that it sucks the foam into the tubing as it spills over the neck. Before it can even reach the bottom of the cup. Eventually the foam reduces to liquid which fills the scrubber

I know there's some folks that install a float valve through the lid to cut this off. I positioned my hole outside of the lid's catch ring but still inside the cup so this wasn't necessary. As I mentioned, I was having this issue where the foam was still ending up in the tube, but I raised the scrubber up and made the line as vertical as possible. This has completely stopped the issue.


I know the line is still dirty, I didn't clean it after I fixed the issue. When it was lower though, I was dumping raw skimmate out of the scrubber almost daily and having to unhook that line from the scrubber to dump skimmate out of the line as well. It wasn't great. Hasn't been an issue since!