Why isn’t potassium in AFR or Tropic Marin A- and K+?

[Randy Holmes-Farley]

I can confirm that my cheato refugium consumes about 20 gram PotassiumChloride in a month. I made for this a daily dose which is checked via a potassium hometest (Salifert or Colombo) and icp ..... Volume refugium is about 50 liters and the total system is about 700 liters ..... I do once a month a WC of 5% with Tropic Marin pro reef salt ..... lightning time refugium is 12 hours .... target value is always 400 ppm

Is that based on analysis of the chaeto, or a change in water levels?

The reason I ask is that the N and P needed to grow that chaeto comes from foods, typically, and those foods may have a similar amount of K in them, leading to a balance in K concentration.

 

[areefer01]

Yes, K is the German version of cation. Maybe it’s only funny to a chemist. Chemistry has little inherent humor. lol

I wonder if there is a potential for error similar to what JPL ran into with the Mars orbiter. Location versions.

In the case of JPL one team used imperial units while the other used metric for some critical calculations which lead to, well, a burn up. Glad that wasn't a meeting I had to attend...

 

[areefer01]

The only cases I know there it ha been said that its necessary to dose K is in zeolite based systems. It seems like zeolite can adsorb K. I have also read about that large refugium can take up some K. K = potassium

I am among those that try to run my system with rather low K concentrations - below 400. During the last 15 years - I have had 2 major occasions with fish death - in both cases - I had K concentrations above 500. I´m not 100% sure that it is the potassium concentrations that is responsible for this but IMO - it close enough to suspect this.

Of some reasons - my tank tend to accumulate K and therefore I now and when does WC with Oceamo corrector and exclude the K part (you ad K separately in this salt)

Sincerely Lasse

Here is my mixed reefs history of potassium. When the system was new or didn't have very large colonies it was below 400. Now the 95th percentile is 445 with the most recent ICP (1/3/2025) reporting 439. The ICP I sent off in December using water from Fiji came back at 415.

I am not really going to worry about it.

Edit: this is using AFR and water changes using TM pro reef salt at 2 to 3 week intervals.

 

[Randy Holmes-Farley]

I wonder if there is a potential for error similar to what JPL ran into with the Mars orbiter. Location versions.

In the case of JPL one team used imperial units while the other used metric for some critical calculations which lead to, well, a burn up. Glad that wasn't a meeting I had to attend...

My brother is lead scientist on the current rover. Fortunately he can work remotely because some neighborhoods around jpl are devastation zones.

 

[areefer01]

My brother is lead scientist on the current rover. Fortunately he can work remotely because some neighborhoods around jpl are devastation zones.

Wishing your brother and family all the best for them and their safety along with calm weather. My former unit just dispatched 8 aircraft to help down there. It is crazy

 

[Marc Pardon]

Is that based on analysis of the chaeto, or a change in water levels?

The reason I ask is that the N and P needed to grow that chaeto comes from foods, typically, and those foods may have a similar amount of K in them, leading to a balance in K concentration.

Change in levels measured in the water ....

 

[Randy Holmes-Farley]

Change in levels measured in the water ....

Ok, so is it counting corals and other organisms too?

 

[Marc Pardon]

Ok, so is it counting corals and other organisms too?

yes (I should rewrite : my system uses 20 gram .....with a refugium)

 

[Randy Holmes-Farley]

Wishing your brother and family all the best for them and their safety along with calm weather. My former unit just dispatched 8 aircraft to help down there. It is crazy

Safe, yes. House is one of a few standing amidst destruction, but is presently unlivable and will be for some time. Thanks.

 

[joseph.timbs]

Currently I have a normal 3 compartment 10 gallon sump on my 40g. Kind of have a little experiment going with the middle compartment. Lit by eBay grow light. Started as a regularly harvested chaeto refugium but my harvesting slowed and stopped completely. I was ok with it since my system is and has been stable for a while. I really don’t think it’s chaeto is growing anymore, but if the growth has stalled, the consumption of K and iron would lock up and cap as well right? It’s pretty much a living mechanical filter, with pods and a ton of bristle worms and helps PH.

 

[Randy Holmes-Farley]

No idea what you mean by K lock up. It isn’t added by afr. Iron consumption will decline, but rising iron is no concern. Some folks dose huge amounts that you could never attain with AFR.

 

[joseph.timbs]

No idea what you mean by K lock up. It isn’t added by afr. Iron consumption will decline, but rising iron is no concern. Some folks dose huge amounts that you could never attain with AFR.

it might be a false assumption on my part. I figured it would soak up the potassium and iron and keep it or “lock”. That’s the way I understood the absorption of nitrates/phosphates and an exporting the nutrients out when harvested. So ur saying it will use the potassium/iron and deplete.

 

[Randy Holmes-Farley]

it might be a false assumption on my part. I figured it would soak up the potassium and iron and keep it or “lock”. That’s the way I understood the absorption of nitrates/phosphates and an exporting the nutrients out when harvested. So ur saying it will use the potassium/iron and deplete.

There’s a huge amount of potassium in seawater. Whether depleting or accumulating, it moves quite slowly.

Iron is going into many different places, including corals, algae, and abiotic precipitation.

 

[joseph.timbs]

There’s a huge amount of potassium in seawater. Whether depleting or accumulating, it moves quite slowly.

Iron is going into many different places, including corals, algae, and abiotic precipitation.

I do 10-15% water changes a week, also AFR, from the thread I’m guessing that’s good enough for potassium. Iron too?

 

[Randy Holmes-Farley]

I do 10-15% water changes a week, also AFR, from the thread I’m guessing that’s good enough for potassium. Iron too?

AFR adds no potassium, and I expect you do not have any need for it.

It may/probably adds enough iron, but that’s a more complicated question.

 

[joseph.timbs]

AFR adds no potassium, and I expect you do not have any need for it.

It may/probably adds enough iron, but that’s a more complicated

I have 55+ corals in my mixed 40g, I did an ICP and it was pretty low that’s what led me to check if AFR had potassium. I did a 50% water change and a couple 25% since along with the usual wc’s. I probably shouldn’t have but dosed a lil of my old Red Sea 4 part’s potassium a few times. I think it might be time for a new ICP, my corals seem healthy and acros still growing tho

 

[rtparty]

Yes, K is the German version of cation. Maybe it’s only funny to a chemist. Chemistry has little inherent humor. lol

You know the old classic? What do you do with a chemist when they die?

 

[Randy Holmes-Farley]

You know the old classic? What do you do with a chemist when they die?

My favorite useless shine additive. Lol

 

[Randy Holmes-Farley]

For those who didn’t get the joke…

What do you do with a chemist when they die?

Barium

 

[Reefering1]

For those who didn’t get the joke…

What do you do with a chemist when they die?

Barium

Lol. I thought it was something about "argon"..