The first ICP after I stopped using the refugium and CO2 scrubber.
First, a couple of observations are administrative. I have had a few discussions with the Route 66 coral farm which is the new ICP collection point on the West Coast (closer than CoralVue in Lousiana), and is supposed to improve the shipping times to Germany.
It took 8 days from the time I shipped my sample to receiving the results. One day of this is counted as a one-off delay by Fed Ex in Germany. Therefore, it is very realistic going forward to receive results in 7 days. They ship Tue and Thu, the same as CoralVue, and if it arrives in the morning of Tue or Thu, they will still ship it on the same day. I would love to get the results faster, but this is as fast as it gets with this process, unfortunately - curious about the Triton turnaround times.
I was planning to recommend to Fauna Marin to offer pre-paid shipping labels for the US - since we all love convenience here
- but I realized it would not be possible for them, since they have multiple collection points, and the label would need to be tailored to one specifically - and this would not fly with East Coast customers since they are getting their results back rather quick. I agree with
@derek_SR is rather annoying and I loved just dropping off the sample at a mailbox vs the post office.
I currently have an ICP consultant based in Europe who helps me with the interpretation of results and next steps. While I feel very comfortable with most of the content in there, there are sometimes trade-offs and considerations when it comes to dosing where I struggle to determine the next best steps.
Impact on PH caused by the removal of the refugium and CO2 scrubber (and previous use of Kalkwasser)
The main topic for this ICP was the impact on PH caused by the removal of the refugium and CO2 scrubber. C02 values were significantly elevated, and I am dosing a rather large amount of alkalinity daily compared to how my tank is stocked. Despite applying the BOLUS method in dosing, I do not see the expected pattern in alkalinity (step down or flat alkalinity over 8-10 hours). Unfortunately, the analysis of this issue is not trivial and comes back to how PH is being regulated in seawater. I share below some considerations that a few might find interesting - I did, as it aligns with the German literature I have been reading on this topic recently.
PH buffer system
The buffer system is there to regulate the pH to prevent a change. In the sea, the buffer system is so effective that the pH barely changes at all. When we dose alkalinity we are aiming to provide enough bicarbonate to replenish the buffer system to prevent a change in alkalinity from day to day. Without sufficient carbon in the buffer system, the pH is not able to be regulated. In an aquarium, the pH shifts because the dynamics are more extreme than in the sea. We have a very limited volume of water, a high ratio of biomass and waste to the volume of water, a high percentage of bacteria and microbial activity to the volume of water, and the surface area to water volume ratio is much higher.
The pH is really the result of factors that raise the alkalinity versus forces that drag down the pH; those would include:
- decomposition of fish waste
- coral growth
- feeding the tank and the resulting bacterial activity from it
- reverse photosynthesis
- deficits in nighttime bicarbonate reserves where CO2 has be brought in from the air/water interface
- all forms of bacteria and microbial action
- carbon dosing
- anaerobic activity or rotten spots in the aquarium that are deprived of oxygen
- the action of Henry’s law where the water must equilibrate with the CO2 level of the room that it is in.
The use of a CO2 scrubber forces the production of precipitation; it is common to see buildups of calcium carbonate in the venturi of the skimmer when using CO2 scrubbers because the media is slowing down the natural regulation of CO2 input into the aquarium, which leads to excess carbonate when localized in the area the air is coming into the skimmer (and under higher pressure) the carbonate will deposit onto surfaces.
In my case, I seem to have quite high bacterial activity on my surfaces. A CO2 scrubber has a similar effect to dosing kalk in creating this problem. Since I used Kalkwasser in the past, and CO2 until recently, this is the effect. Surface deposits produce excess biofilms that result in acidification of the water. For additional context, my current alkalinity consumption relative to my water volume is almost double (!) that of a well-stocked coral farm - to make up for all the PH-dragging activities in my tank.
There is no simple solution to this, but it will get better over time - in fact, in the past couple of weeks, I have already seen a continuous improvement compared to when I took off both the scrubber and the refugium. PH goes up now naturally to 8.22 (post calibration of probe) and does not drop below 8 - without Kalkwasser or any other supplement (!), while the system is still fighting with the fallout of previous use of Kalkwasser and CO2 scrubber.
Detailed observations from the ICP report
- Salinity: A disappointing result was that my salinity was slightly off. If salinity is off, so are trace elements. I determined the root cause to be that the time it takes during the colder months for the temp acclimation to work with the Milwaukee refractometer is longer than the 1 minute I typically wait before I accept the results. I have adjusted this now to 2-3 minutes and there is 1 point difference when doing this, more aligned with the ICP.
- No elements have concerning high levels but some continue to be low despite additional dosing. Some of this was due to calculation errors I made. However, others that were 0 for some time have finally gone up, so this is promising.
- Btw, SAK is similar to DOC and looks rather good.
- I will mostly use Captiv8 elements for the corrections except for copper, which I will adjust with Fauna Marin elementals Cu.
Overall, I personally get a lot of value from these regular ICPs but the main activity is to get PH back on track the 'natural' way, and optimized traces are critical in this journey. Specifically Calcium, Strontium, Potassium, Barium, and Iron are all precipitation risks when too high, and would extend the journey of high PH if not managed properly.