PH and CO2 scrubbers

PghReef · Jan 17, 2022

How many use them? Everything I read has very conflicting information regarding ph and whether or not to test for or attempt to rectify low pH. Many say it is fine to run a low pH system, and many others say you must correct pH to achieve healthy corals and good growth. I find it hard to decipher all the conflicting information out there, yet we're concerned about acidification of the oceans and mass bleaching events.

I run 90 gallon with sump. Alk is 8-8.5 using soda ash as my supplement. Open tops and skimmer run 24/7. My pH with my probe averages about 7.9 at night and 8.05 during the day. Corals seem healthy but growth isn't anything to brag about. My euphyllia always have baby heads but I've never seen them grow into full sized heads.

Should I invest in a co2 scrubber? Can there be any possible negative effects from adding one to the system?

PeterC99 · Jan 17, 2022

I also have a 90g and had same pH issues. Added a CO2 scrubber and now my pH is significantly higher and corals growing like crazy. Below are my results and that’s WITH a Calcium Reactor that’s putting in low pH effluent back into my sump.

Spare time · Jan 17, 2022

I can't think of a negative. Its changed out frequent sorta like carbon. I think that low pH (7.8) should be best described as decently tolerable but borderline problematic. Your pH isn't terrible, but I do believe that you may find growth benefits from a higher pH. If it isn't much of a hassle to set one up, then I say go for it

PghReef · Jan 17, 2022

So what do you do exactly, I have a reef Octopus skimmer that runs with the. silencer it has the clear little jar thing hooked to the side, 1 tube on bottom goes to the venturi I believe and there's 2 stubs on the top for air intake. 1 is covered and q is open.

Just connect the tubing from the co2 scrubber to the top of the silencer?

PghReef · Jan 17, 2022

PeterC99 said:
I also have a 90g and had same pH issues. Added a CO2 scrubber and now my pH is significantly higher and corals growing like crazy. Below are my results and that’s WITH a Calcium Reactor that’s putting in low pH effluent back into my sump.

Beautiful tank btw. I cant keep montis alive for anything but my acros do ok. Maybe they're more sensitive to low pH? Not sure

Spare time · Jan 17, 2022

PghReef said:
So what do you do exactly, I have a reef Octopus skimmer that runs with the. silencer it has the clear little jar thing hooked to the side, 1 tube on bottom goes to the venturi I believe and there's 2 stubs on the top for air intake. 1 is covered and q is open.

Just connect the tubing from the co2 scrubber to the top of the silencer?

This is one way to do it

Here is another

hllb · Jan 17, 2022

I think it’s worth trying a scrubber but mine didn’t make a large difference. It certainly is helping, but I’m still only running about 7.95 to 8.05 most days. I had three days where it ran 8.0 to 8.15 and I was thrilled but then it dropped again and I haven’t been able to get it back up in that range.

BroccoliFarmer · Jan 17, 2022

I literally just installed a recirculating scrubber this morning. Ugly little DIY project..but seems to have helped others.

GillMeister · Jan 17, 2022

I started using one last year and it raised my pH range from 7.8-8.1 to 8.1-8.3. It's measurable and significant. It does, however, require that you change the soda lime regularly and proactively. Otherwise, it can start releasing captured co2 back into the system. Mine gets changed out monthly.

PghReef · Jan 17, 2022

GillMeister said:
I started using one last year and it raised my pH range from 7.8-8.1 to 8.1-8.3. It's measurable and significant. It does, however, require that you change the soda lime regularly and proactively. Otherwise, it can start releasing captured co2 back into the system. Mine gets changed out monthly.

Do u change it when u see pH creeping back up or is there a color changing resin like DI resin?

BroccoliFarmer · Jan 17, 2022

PghReef said:
Do u change it when u see pH creeping back up or is there a color changing resin like DI resin?

BRS has color changing media.

Color Changing CO2 Absorbent Media

Raise your Reef Tank's pH by controlling Carbon Dioxide! Bulk Reef Supply Color Changing CO2 Absorbent Media (Soda Lime) is the perfect solution if your aquarium has a low pH but proper alkalinity levels. It is most commonly used by connecting a carbon dioxide scrubber to your protein skimmer's...

www.bulkreefsupply.com

GillMeister · Jan 17, 2022

PghReef said:
Do u change it when u see pH creeping back up or is there a color changing resin like DI resin?

When it has turned approximately 60% blue you should change to new media. At least that works for me. Now i just change it on a regular schedule based on historical trending.

wmb0003 · Jan 17, 2022

IS it feasible in your situation to run a fresh airline outside somehow? This will give the same effect as a co2 scrubber without the need to change the media.

PghReef · Jan 17, 2022

wmb0003 said:
IS it feasible in your situation to run a fresh airline outside somehow? This will give the same effect as a co2 scrubber without the need to change the media.

Not unless I drill through walls and brick. I never planned on correcting pH as so many say if you're above 7.8 you're fine, but I'm really wondering if that's a huge reason why I don't see great growth.

BroccoliFarmer · Jan 17, 2022

PghReef said:
Not unless I drill through walls and brick. I never planned on correcting pH as so many say if you're above 7.8 you're fine, but I'm really wondering if that's a huge reason why I don't see great growth.

Lower PH for SPS and LPS does slow down growth (in fact, if it gets too low the water turns acidic and the coral bone structure will 'melt'..same concept as a calcium reactor). Above 7.8 your corals WILL grow..be it slower than higher PH (all other things being equal)

fushi · Jan 17, 2022

I believe Ph is extremely important! Keeping a higher PH does increase growth but more importantly I believe it makes corals hardier, decreasing damaging effects from major parameter swings.

As for the CO2 scrubber anecdotally they work and @telegraham recently posted a scrubber test that showd almost a 50% reduction of CO2.
I believe pulling outside air is far more cost effective and better in the long run, so you should try to figure out a way to do that before going with the scrubber. (You could run a cheap 1/2 in tube to a window if drilling through brick isn't in the cards)

For the CO2 scrubber media I recomend two little fishies, other brands dont seem to change color well or even at all. From my experience the BRS media doesn't change color and is dusty and the icecap media barely changes color like little speckles.
The TLF media tends to be more expensive so you can buy a some TLF and some icecap (or any pelletized type of) media and just fill the top section of your scrubber with TLF media so you know when to change it. Alternativly you can just wait untill your PH starts dropping.

It should also be noted that low PH can also be caused by other factors besides high in house CO2, but the majority of the time high in house CO2 and or too small of a skimmer is the main issue.

An alternative route is to use a high PH 2 part

This recipe has an extremely strong ph boost, just be extra careful with lye.
https://www.reef2reef.com/threads/second-new-diy-two-part-recipe-with-higher-ph-boost.357080/

"You can use this calculator and the Alk entry for Randy's Recipe #1:
http://reef.diesyst.com/chemcalc/chem_calc3.html"

I just buy the Calcium part from BRS
https://www.bulkreefsupply.com/7-pounds-bulk-calcium-chloride-bulk-reef-supply.html

And buy the Sodium Hydroxide from Amazon

After I reached my PH goal dosing Sodium Hydroxide but needed to suppplement more Alkalinity I dose BRS Soda Ash.
https://www.bulkreefsupply.com/7-pounds-bulk-soda-ash-bulk-reef-supply.html

I hope this helps