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