Advantages of lowering CO2/Constant PH at 8.2x?

[Faulkner’s maze]

Hello Randy!
So my question is about artificially maintaining a constant PH at 8.2x by way of combining CO2 absorption media with a solient valve to make sure it doesn't go over the desired PH level-

My current PH level ranges 8.04-8.16. With the media, it could easily elevate it past 8.3 which I know would start increasing alk/calc precipitation. So the solient valve would cap it especially at the higher end.

Alk ranges about 7.5-7.7 dKh in the last few measurements. Calc at ~400 ppm. 0

1) I am particular interested in whether a constant PH at 8.2x would benefit coral growth
2) Would this help inhibit certain unwanted algae growth (namely bubble algae/diatom) by additional nutrient removal.

The reason I ask about #2 is that phosphates are at .07 and I am about to employ a new microalgae reactor to take the refugium light offline as to decrease the cyanobacteria that keeps infesting the sump. Previously it was "free" floating which did a great job of taking phosphate to 0 but there was a concern about pumps/impellers jamming so I put in it a media container and not as effective.
I also want to starve those little bubble algae clusters best I can.

 

[Randy Holmes-Farley]

I doubt holding it at pH 8.2 would be better than letting it go higher, but there's not much evidence around. It's certainly a fine experiment and/or a way to save media.

It may get easier for corals to calcify at higher pH (higher than 8.2) because they can more easily pump out H+, but whether that really benefits them or not, I'm not sure.

Some algae may begin to suffer at higher pH due to lack of CO2, but other algae species use HCO3- as a source of CO2, so it may not hurt them as much.

 

[Faulkner’s maze]

I doubt holding it at pH 8.2 would be better than letting it go higher, but there's not much evidence around. It's certainly a fine experiment and/or a way to save media.

It may get easier for corals to calcify at higher pH (higher than 8.2) because they can more easily pump out H+, but whether that really benefits them or not, I'm not sure.

Some algae may begin to suffer at higher pH due to lack of CO2, but other algae species use HCO3- as a source of CO2, so it may not hurt them as much.

Ok -good to know. Thanks.

 

[Randy Holmes-Farley]

You're welcome.
Let us know if you implement it, and how it works out.

Happy Reefing.

 

[Faulkner’s maze]

You're welcome.
Let us know if you implement it, and how it works out.

Happy Reefing.

Will do if I go that route-although how do you “quantify” coral growth? ;-)

 

[Randy Holmes-Farley]

Will do if I go that route-although how do you “quantify” coral growth? ;-)

Without a lot of monitoring (say, by pictures over time), it will be hard, but anything from "I saw nothing" to "I think my tank never looked better" or "It seemed to go downhill" are worth hearing.

If you do not see a difference, is it worth doing?

 

[Cory]

I doubt holding it at pH 8.2 would be better than letting it go higher, but there's not much evidence around. It's certainly a fine experiment and/or a way to save media.

It may get easier for corals to calcify at higher pH (higher than 8.2) because they can more easily pump out H+, but whether that really benefits them or not, I'm not sure.

Some algae may begin to suffer at higher pH due to lack of CO2, but other algae species use HCO3- as a source of CO2, so it may not hurt them as much.

It never occured to me that co2 could be a limiting nutrient in some reef tanks inhibiting algae. Thsts really interesting. Possibly a side benefit of co2 removsl media?

 

[Randy Holmes-Farley]

It never occured to me that co2 could be a limiting nutrient in some reef tanks inhibiting algae. Thsts really interesting. Possibly a side benefit of co2 removsl media?

Photosynthesis and the Reef Aquarium, Part I: Carbon Sources by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-10/rhf/index.php

see Table 1

 

[Faulkner’s maze]

Without a lot of monitoring (say, by pictures over time), it will be hard, but anything from "I saw nothing" to "I think my tank never looked better" or "It seemed to go downhill" are worth hearing.

If you do not see a difference, is it worth doing?

I was thinking along the lines of...never mind..I’ll let everyone know what happens if I go forth with it.


What I will say is the amazing capability of Cyanobacteria to drag down PH. By letting it go for a couple of weeks as work got in my way, and then cleaning it-my PH jumped back from ~8.05 to 8.15 (top range) so I am eager to get that refugium light offline.

In addition to the doser that will be set up to hopefully equalize PH overnight a bit better in addition to more stable alk than manually dosing sodium carbonate that spikes the ph (not too much but still) -those steps are first.

The fun never does stop...

 

[Faulkner’s maze]

Photosynthesis and the Reef Aquarium, Part I: Carbon Sources by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-10/rhf/index.php

see Table 1

Fascinating article. Thanks for sharing.

I would be interested in CO2 sensitivity of Valonia-which prompted my interest in CO2 reduction in the first place...