Oceamo Skimmate Analysis Results Discussion

[vahegan]

If you have a good gas exchange otherwise, a skimmer is unnecessary in my eyes.

Yes, I believe that oxygenation is an important factor and also helps to keep the redox high. However, the skimmer also dissolves a lot of CO2, which results in pH drop, especially in the absence of photosynthetic activity at night. I suspect that not using a skimmer may result in higher pH values (is that your observation in those skimmerless systems?), which the corals like. Instead of going completely skimmerless, it would be interesting to try weak skimming, or going with old-school airstone driven skimmers - I think that Sander still makes them? Or maybe a weak skimmer with CO2 scrubbing.

This may be subject to change. In the first decade of this century we had low sells of K+ Elements in the US because everyone thought trace metals are all toxic.

Well, they are toxic Depending on dose, of course: like everything else

Also all ICP-labs gave "green lights" with no detectable transition metals until recently. It only started to change in the last few years while lowering the detection limits of ICP-OES also. I think the introduction "through the backdoor" with All-For-Reef was successful and contributed to the change in view of the transition metals. You should be able to retrace this when going back in the discussions of this forum.

Interesting. Are formates of those elements soluble?
I was experimenting with dosing organic salts of trace elements, namely gluconates, but didn't continue the experiments for long enough as I has a dino outbrake and had to fight that for quite a few months. Don't know whether that was anyhow linked to dosing traces, probably not, it could have rather been promoted by my amino mix - very unscientific attitude on my side, to try two different things simultaneously

This would be the theory based on the results of Dan_P. This is only true initially until the surfaces of the sand are saturated. Then adsorption should drop to zero or an ion exchange of for example Fe(III) against Zn(II) occurs.

I wonder if, after reaching saturation, this sand would then be leaking traces back into water, serving as a buffer for a more or less stable concentration in water.

 

[vahegan]

It's funny, I have finished my post and saw another comment that was posted moments before by GARRIGA, where he says almost the same thing about using airstone driven skimmers and CO2 scrubbers

 

[GARRIGA]

Old school airstone how some wholesalers and breeders and Koi keepers still aerate their water. Just not sure how it will equalize with high room co2 or perhaps it gasses off co2 faster than equalization with room air happens. Fact those with my situation see improved pH when scrubbing co2 air into the skimmer leads me to believe that is plausible.

 

[vahegan]

Old school airstone how some wholesalers and breeders and Koi keepers still aerate their water. Just not sure how it will equalize with high room co2 or perhaps it gasses off co2 faster than equalization with room air happens. Fact those with my situation see improved pH when scrubbing co2 air into the skimmer leads me to believe that is plausible.

Yes, the volume of air driven through an airstone is much smaller compared with what the needlewheel pump draws and a simple scrubber filled with sodium hydroxide should last quite longer.
For a while, I have been thinking how to reduce the CO2 draw in my skimmer to reduce pH drop at night. I did not want to use recirculation, because that would also reduce the oxygenation, but using a CO2 scrubber would also not be a good option as the media would soon be depleted by drawing over 1000 liters of air through it every hour. I ended up dosing kalk slurry at night (as my main KH/Ca source) to compensate for pH drop.

 

[Lasse]

However, the skimmer also dissolves a lot of CO2, which results in pH drop, especially in the absence of photosynthetic activity at night. I suspect that not using a skimmer may result in higher pH values (is that your observation in those skimmerless systems?),

Not true in a mature system. In these - the internal CO2 produktion is high and produce very much CO2 and the gas exchange in order to keep the pH up is very important. Note the pH drop when my skimmer stop during the night (red marking) and how it rise when I discovered seven o´clock in the morning

Sincerely Lasse

 

[vahegan]

Not true in a mature system. In these - the internal CO2 produktion is high

That's an interesting point and an interesting experiment to run.
I was assuming that the nightly drop was purely due to CO2 intake from the air not being compensated by photosynthesis, but the skimmer failure on your diagram seems to prove that respiration has a strong effect of its own. I should try to see if I can reproduce that drop, and I am also using GHL Profilux.
Are the "teeth" on your graph due to dosing? I am seeing similar teeth when I dose kalk slurry, but unfortunately GHL only allows up to 24 individual doses per day (I know that it is possoble to set up a virtual doser to extend the number but that is too complicated for me)

 

[Randy Holmes-Farley]

Skimmers can raise or lower CO2 and pH in any system, and frequently does both at different times of the day.

 

[Lasse]

In a normal set up indoors the equilibrium pH between CO2 in the water and the air a pH is between 8 - 8.1 - lower if there is high CO2 in the room. This means that normally the skimmer vents CO2 when the pH is below 8 and adds when the pH is above - IME

Are the "teeth" on your graph due to dosing?

Yep - I dose Triton Core7:3a+b during night time (27 times as it is now) . It is set up with another (virtual) doser on automatic 48 doses/day but with help of a PL - it is set by a timer only to dose between 21:45 - 11:15

Sincerely Lasse

 

[GARRIGA]

But is the reason the skimmer is lowering co2 perhaps because during photosynthesis there's less to expel then would be gained through equilibrium with high room co2 vs nighttime when tank co2 would be at it's highest therefore unable to gas it off quicker than gained through equilibrium?

This is how I'm trying to logically explain it to myself yet @Lasse experienced pH drop at night when skimmer had been off although not aware of his house dynamics as far as indoor co2 levels.

Trying to rationalize this without having a brain freeze episode. Obviously once I have a controller hooked up I can see how my situation plays out although I'll more likely be running just an aerator vs skimmer but affect of how co2 is gassed in general should be relatively similar.

 

[vahegan]

I have Ambient Weather AQIN sensor which monitors CO2 levels in the same room where my tank is. I also have GHL Profilux pH probe monitoring tank pH constantly. I can export both as CSV. I can turn off the skimmer for one night, then superimpose the CO2 in air graph over the pH graph with skimmer on and skimmer off. This should clarify things a bit.

 

[Hans-Werner]

Well, they are toxic Depending on dose, of course: like everything else

So many things may be toxic, depending on dose. How often do you hear about iron deficiency, nevertheless it may be toxic. But a number of transition metals are also essential. You always have to see both sides.

Interesting. Are formates of those elements soluble?
I was experimenting with dosing organic salts of trace elements, namely gluconates, but didn't continue the experiments for long enough as I has a dino outbrake and had to fight that for quite a few months. Don't know whether that was anyhow linked to dosing traces, probably not, it could have rather been promoted by my amino mix

Yes, most organic salts of the essential transition metals are soluble and may form complexes like Fe-(III)-citrate. Copper citrate is said to be more toxic to algae and more effective as a treatment than inorganic copper salts.

I wonder if, after reaching saturation, this sand would then be leaking traces back into water, serving as a buffer for a more or less stable concentration in water.

Interesting thought. Maybe this should be tested. It would contribute to more stable conditions of tanks with aragonite substrate vs. bare bottom tanks.

 

[Lasse]

I have Ambient Weather AQIN sensor which monitors CO2 levels in the same room where my tank is. I also have GHL Profilux pH probe monitoring tank pH constantly. I can export both as CSV. I can turn off the skimmer for one night, then superimpose the CO2 in air graph over the pH graph with skimmer on and skimmer off. This should clarify things a bit.

You mean something like this

My skimmer take air from the outside and its filtered trough a CO2 scrubber before it enter the skimmer. The aquarium is open, sump is open and affected by the ambient concentration of CO2 in the room. We are only 2 people (however my cat should say that it have two butlers) in the flat and CO2 vary between 400 and 1000 ppm. Normally - during winter (closed doors and windows) CO2 is normally around 550 - 1000 ppm - if we aew away during a couple of days the CO2 drops to ambient outside concentration - around 400 ppm. We was out of town the 28/12 2024 Ph min - 8 and max 8,10. The addition of Triton Core7:3 a+b hold up the night pH with around 0.1 pH unit IME

During the 28/12 my room CO2 looks like this

The absolute pH measurements should be taken with a grain of salt because it was a time since calibration but it shows the tendency of my system.

Sincerely Lasse