Skimmer for gas exchange

[KonradTO]

Hi all,
After realizing my pH was much lower than where I want it to be (7.7 at lights off, 7.6 during blackout), and that the reason was low gas exchange, I finally decided myself to get a skimmer. Only problem: I struggle to keep nutrients detectable without dosing and I did not want to lower my NO3 input even further.
So what I am trying is to flush directly the skimmate (super wet, basically it would fill the cup in 30 seconds) back in the sump, over some sponge filter, which get rids of the bigger bubbles).
So far it seems working (see pics below)

pH went from 7.72 to 7.85 in less than 24h and seems increasing further hour by hour.
Notice that I am doing a blackout right now so there is none of the typical day/night fluctuation. Once I turn lights off I expect the effect to be even more noticeable.

Some background:
15g sump/fuge with tons of macros
32g display with acrylic lid
Chinese 80$ skimmer
pH after cup experiment: 8.1!!

 

[T-J]

Why not just add an airpump and airstone instead of a skimmer?

 

[KonradTO]

Why not just add an airpump and airstone instead of a skimmer?

I actually did. Well end of the story it does not work as good as the skimmer. I never had a skimmer before but now I understand why they are good for gas exchange, the foam made by the skimmer is totally different from the airstoon (even wood ones). Also now I modified my acrylic lid and made it partially open with some mesh. I will check back in a week how much gas exchange improved with a further cup&airstone test.

 

[KonradTO]

After 48h I can say that I am happy with the pH values, but on the other hand I am getting unexpected patterns.
I probably will have to double check if the probe is still calibrated but I am hovering constantly at around pH 7.98-8.02, without the usual fluctuations. I have also to say that I am slowly ramping up the lights to the old settings, maybe the low light intensity is preventing the photosynthesis from outcompeting with the skimmer for gas exchange. It will be interesting to see what will happen once the lights will be back to usual regime. Maybe there is a threshold at which light is strong enough to stimulate algae to further deplete CO2 during the day.. and the same might be true for the fuge.

 

[DeeFromBrooklyn]

Hi all,
After realizing my pH was much lower than where I want it to be (7.7 at lights off, 7.6 during blackout), and that the reason was low gas exchange, I finally decided myself to get a skimmer. Only problem: I struggle to keep nutrients detectable without dosing and I did not want to lower my NO3 input even further.
So what I am trying is to flush directly the skimmate (super wet, basically it would fill the cup in 30 seconds) back in the sump, over some sponge filter, which get rids of the bigger bubbles).
So far it seems working (see pics below)

pH went from 7.72 to 7.85 in less than 24h and seems increasing further hour by hour.
Notice that I am doing a blackout right now so there is none of the typical day/night fluctuation. Once I turn lights off I expect the effect to be even more noticeable.

Some background:
15g sump/fuge with tons of macros
32g display with acrylic lid
Chinese 80$ skimmer
pH after cup experiment: 8.1!!

Do you have a screen top? Glass tops tend to hender oxygen exchange. Upper skimmer needs adjustment. Cheaper skimmer benefit from a shutoff valve on the air intake line if the general control isn't reducing the wet foam

 

[KonradTO]

Do you have a screen top? Glass tops tend to hender oxygen exchange. Upper skimmer needs adjustment. Cheaper skimmer benefit from a shutoff valve on the air intake line if the general control isn't reducing the wet foam

In this case I am "wet foaming" on purpose. My idea is to oxygenate as much water as I can. Basically the water enters the skimmer and directly leaves from the drain.

 

[Duncan62]

Hi all,
After realizing my pH was much lower than where I want it to be (7.7 at lights off, 7.6 during blackout), and that the reason was low gas exchange, I finally decided myself to get a skimmer. Only problem: I struggle to keep nutrients detectable without dosing and I did not want to lower my NO3 input even further.
So what I am trying is to flush directly the skimmate (super wet, basically it would fill the cup in 30 seconds) back in the sump, over some sponge filter, which get rids of the bigger bubbles).
So far it seems working (see pics below)

pH went from 7.72 to 7.85 in less than 24h and seems increasing further hour by hour.
Notice that I am doing a blackout right now so there is none of the typical day/night fluctuation. Once I turn lights off I expect the effect to be even more noticeable.

Some background:
15g sump/fuge with tons of macros
32g display with acrylic lid
Chinese 80$ skimmer
pH after cup experiment: 8.1!!

Are you still running a refugium? Running lights 24 hrs helps eliminate the night time dip. Set up looks good.

 

[KonradTO]

Are you still running a refugium? Running lights 24 hrs helps eliminate the night time dip. Set up looks good.

Yes I run fuge lights with a 1h overlap with DT light, morning and evening. So far it is working fine,
After a couple of days pH stabilized, I get an almost flat line hovering between 7.98 and 8.03 pH. I expected a tiny bit higher pH after I added the skimmer, but I am happy with the results so I will leave it like this for now.

edit. I have been running the fuge for months, and still I had huge fluctuations in pH and overall low values. I cannot tell whether with more intense light this would have been improved, but so far the thing that worked the best was the skimmer.

 

[Duncan62]

Yes I run fuge lights with a 1h overlap with DT light, morning and evening. So far it is working fine,
After a couple of days pH stabilized, I get an almost flat line hovering between 7.98 and 8.03 pH. I expected a tiny bit higher pH after I added the skimmer, but I am happy with the results so I will leave it like this for now.

edit. I have been running the fuge for months, and still I had huge fluctuations in pH and overall low values. I cannot tell whether with more intense light this would have been improved, but so far the thing that worked the best was the skimmer.

You've come a long way with this tank. I've found the 24 hour light works best for me hut the idea is the same. And it helps. Have you got any of those cool original macros from your original in tank set up? Best wishes.

 

[KonradTO]

You've come a long way with this tank.

Thanks Duncan! It's being the hardest of my previous experiences with aquariums and terrariums. Next time dartfrogs terrarium, much less work XD

I've found the 24 hour light works best for me hut the idea is the same. And it helps.

Do you notice better growth in the fuge with a 24h day cycle? I recall from some botany lecture that plants grow better with some dark cycle, peaking at maybe 16:8 or something like that. But we are talking about algae, which are different of course.
But yea the fact that I see almost no fluctuations in pH it means that gas exchange is good right now. Also macros are growing very well in the fuge, slowly but steadily. I recently added a beautiful red Botryocladia*, very curious to see if it thrives. I am on the hunt for a blue hypnea as well.

Have you got any of those cool original macros from your original in tank set up? Best wishes.

Unfortunately the red ones slowly melted away. Same for the Sargassum, but I knew it was difficult.
I recently brought from the mediterranean a small fragment of something like a red hairy Gracilaria specimen, very beautiful, but I am not seeing any growth in months unfortunately. The only ones that survives from the beginning are the Caulerpa prolifera and the brachypus (bleah!).

 

[Duncan62]

Thanks Duncan! It's being the hardest of my previous experiences with aquariums and terrariums. Next time dartfrogs terrarium, much less work XD

Do you notice better growth in the fuge with a 24h day cycle? I recall from some botany lecture that plants grow better with some dark cycle, peaking at maybe 16:8 or something like that. But we are talking about algae, which are different of course.
But yea the fact that I see almost no fluctuations in pH it means that gas exchange is good right now. Also macros are growing very well in the fuge, slowly but steadily. I recently added a beautiful red Botryocladia*, very curious to see if it thrives. I am on the hunt for a blue hypnea as well.

Unfortunately the red ones slowly melted away. Same for the Sargassum, but I knew it was difficult.
I recently brought from the mediterranean a small fragment of something like a red hairy Gracilaria specimen, very beautiful, but I am not seeing any growth in months unfortunately. The only ones that survives from the beginning are the Caulerpa prolifera and the brachypus (bleah!).

The algae scrubbers I run are populated by so many different types . Most of the red and green hair grows much better. Cheato also. The other hair and slime algeas are more efficient than Cheato. It's the only means of filtration in my systems. The constant photosynthesis without the exhale dark period helps pH stability. Using plants for filtration has been my thing since the 80s. That's why I've been so interested in you in tank method. I'm trying one now with scrubber and in tank easy macros. Keep experimenting with algae and plants. Good luck.

 

[KonradTO]

The tank right now:

Coraline is growing much faster since I started dosing calcium as well

 

[DavidinGA]

Ok...why not just dose kalk for higher pH?

 

[KonradTO]

Ok...why not just dose kalk for higher pH?

Because I am already dosing sodium carbonate. But I don't have many corals so the amount I dose does not affect pH much. My tank consumes something like 1 dkH every 3 days. Some people add that within hours

 

[Duncan62]

The tank right now:

Coraline is growing much faster since I started dosing calcium as well

Amazing growth on the glass! Looks great. Needs corals.