Does coral use Alk and Cal consistently

[AltitudeAquarium]

Not really worried about it as its very easily corrected. The reason I brought the question up was it seemed fascinating, does coral consistently use supplements in a controlled environment, or can they splurge every so often and consume more.

To answer your question with a question without sounding like a smart****. Do we humans eat and drink consistently the same day to day? I sure have ravenous pig out sessions under the right conditions. As others have stated, there are other parameters that the corals maybe responding to especially in the limited water "capsule " that we house them in. I think metabolic rates of the fish, the CUC and the other zooplankton may contribute to the coral intake. FWIW.

 

[TX_Punisher]

According to my Trident, no, they do not.

 

[JCOLE]

In my mixed reef I experience minor fluctuations here and there on there uptake. They definitely can use more or less depending on what "mood" there in. In my experience its perfectly normal, as I experience the same in my mixed reef jam packed with corals and fish.

Nice! What are those 3 purple and gold corals at the very bottom? Are those the famous Cry Baby corals? LOL!! I had to....sorry

 

[HB AL]

Nice! What are those 3 purple and gold corals at the very bottom? Are those the famous Cry Baby corals? LOL!! I had to....sorry

Took me a few to figure out what corals you where referring to , 40 year fan here, definitely not a cry baby Laker fan here, maybe if we didn’t have 16 championships, good thing is they look great this year. Laker haters in the house I see

 

[JCOLE]

Took me a few to figure out what corals you where referring to , 40 year fan here, definitely not a cry baby Laker fan here, maybe if we didn’t have 16 championships, good thing is they look great this year. Laker haters in the house I see

Lol! Not a hater just picking. Yes they do look good this year. I was a huge Magic fan when Howard was on the team and he put a bad taste in my mouth when he left. He hasn't made a great impact since bouncing around from teams since he left. However, over these last couple games he has started to become dominant under the boards again. LBJ, AD, and DH are going to make a good combination down low.

Great looking tank by the way!!!

 

[BeejReef]

Great question. I feel like I see something similar in my logs. I only test once a day, but it's 8.4, 8.4, 8.4.. then 8.3, 8.2...

In that example, it normally stabilizes for another 3-4 days at 8.3. I take it as the tank responding to stability and marginally increasing uptake. It happens even if I increase my daily dose. Perhaps it will bump up to 8.6 for a few days, but then the pattern repeats. I'm guessing I'm just in a stage of increasing alk/calc demand and that the test kits are only accurate enough to start registering the change after a few days.

 

[Ferrell]

I have my Mag high for a different reason, plus it seems that HW Marine reefer mix salt has a higher than normal Mag.

Glad to hear it’s not just me but the HW Reefer

 

[blasterman]

Other biologies in your tank eat bicarbonate, and those biologies can vary their alk consumption.

Hard corals dont regulate bicarbonate and carbonate uptake. SPS produce their skeletons by exporting hydrogen ions in a narrow membrane which causes a localized pH increase which causes calcium carbonate to precip at those growth points. Higher tank pH makes it easier for the coral to dump hydrogen ions. As far as I've studied the process corals cant regulate the ratio of bicarb to carbonate although some can resort to different forms of calcium carbonate growth (calcite) In response to higher bicarb levels.

 

[PhreeByrd]

I hope I'm not stating the obvious, but corals don't actually 'consume alk'. Other things in the tank affect the alkalinity level, and corals do seem to be affected by the alkalinity level. But I do not believe the corals are responsible, in any but the most benign ways, for affecting the alkalinity level in the water.

 

[BeejReef]

Other biologies in your tank eat bicarbonate, and those biologies can vary their alk consumption.

Hard corals dont regulate bicarbonate and carbonate uptake. SPS produce their skeletons by exporting hydrogen ions in a narrow membrane which causes a localized pH increase which causes calcium carbonate to precip at those growth points. Higher tank pH makes it easier for the coral to dump hydrogen ions. As far as I've studied the process corals cant regulate the ratio of bicarb to carbonate although some can resort to different forms of calcium carbonate growth (calcite) In response to higher bicarb levels.

Def learned something there. ty

 

[Stigigemla]

10 or 15 years ago I read an article where they had investigated the metabolim of corals.
(I believe it was in Advanced Aquarist) Anyway it stated that the metabolism followed the light period but was delayed 2 or 3 hours both after litght was on and off. Now with the alcalinity monitors I am sure there are some people here that can say how the day shedule are in their tanks.

The consumption or not of alcalinity by corals can be a bit difficult to understand.
Photosyntetic corals that grow consume CO3- which is bound in the skeleton with Ca. That means the alcalinity level will decrease if You dont do anything.
But they also rise the pH wich maybe can be seen as rising alcalinity.

Thats wrong. Alcalinity is measured from how much acid is needed to sink the pH to 4,3.
It has nothing to do with the starting pH when You begin to sink the pH.

 

[Randy Holmes-Farley Verified Community Expert]

As far as I've studied the process corals cant regulate the ratio of bicarb to carbonate

Where are you talking about? This ratio is fixed precisely by pH. Cells can regulate pH, so effectively control this ratio inside of them or anywhere else they impact pH.

 

[Randy Holmes-Farley Verified Community Expert]

I hope I'm not stating the obvious, but corals don't actually 'consume alk'. Other things in the tank affect the alkalinity level, and corals do seem to be affected by the alkalinity level. But I do not believe the corals are responsible, in any but the most benign ways, for affecting the alkalinity level in the water.

Not true. Hard corals consume tons of alkalinity to precipitate calcium carbonate skeletons. It is the carbonate of calcium carbonate that carries the alkalinity.

 

[Randy Holmes-Farley Verified Community Expert]

Other biologies in your tank eat bicarbonate, and those biologies can vary their alk consumption.

Hard corals dont regulate bicarbonate and carbonate uptake. SPS produce their skeletons by exporting hydrogen ions in a narrow membrane which causes a localized pH increase which causes calcium carbonate to precip at those growth points. Higher tank pH makes it easier for the coral to dump hydrogen ions. As far as I've studied the process corals cant regulate the ratio of bicarb to carbonate although some can resort to different forms of calcium carbonate growth (calcite) In response to higher bicarb levels.

As far as I know, whether corals take up carbonate or bicarbonate is not known. Distinguishing them is very difficult and would only be able to be done at the molecular level of transporters and such. Bicarbonate and carbonate interconvert thousands of times a second, so they are not really different entities for long.

 

[Omar Marambio]

In my tank sps tank my corals consume more calcium than alk, I use a calcium reactor and I keep my alk at 8.4 and I thought my calcium would be balance around 450, after my ati test I found that my calcium was around 380 and alk 8.4. So I guess it depends on the tank the consumption.

my tank looks stable and the sps are growing fine

 

[Randy Holmes-Farley Verified Community Expert]

In my tank sps tank my corals consume more calcium than alk, I use a calcium reactor and I keep my alk at 8.4 and I thought my calcium would be balance around 450, after my ati test I found that my calcium was around 380 and alk 8.4. So I guess it depends on the tank the consumption.

my tank looks stable and the sps are growing fine

That cannot be true. There is no coral that consumes more calcium than the proportional amount of alkalinity (about 18-20 ppm calcium for each 1 meq/L (2.8 dKH) of alkalinity.

It may be testing error, water changes, or something else that is adding alk to your tank, but it isn't unbalanced coral consumption.

 

[Omar Marambio]

That cannot be true. There is no coral that consumes more calcium than the proportional amount of alkalinity (about 18-20 ppm calcium for each 1 meq/L (2.8 dKH) of alkalinity.

It may be testing error, water changes, or something else that is adding alk to your tank, but it isn't unbalanced coral consumption.

I am running only a calcium reactor, it maybe that the ATI test was incorrect

 

[Randy Holmes-Farley Verified Community Expert]

I am running only a calcium reactor, it maybe that the ATI test was incorrect

Tap water for top off? Nitrate dosing? Water change with a low calcium mix like ordinary IO? All of those can lower calcium relative to alkalinity.

 

[Stigigemla]

It is sad but normal that calcium reactors leach CO2. So it is a good idea to add Calcium hydroxide in a kalk mixer or dose Sodium hydroxide or carbonate to balance that.
I believe Your test is correct at least to a few percent misreading.