Alkalinity And Calcium Fluctuate through out the day?

[Derrick Picker]

Hello all. I have a calcium reactor which I thought I got tuned in. Ever since I got myself a Neptune Trident I notice that my Alkalinity and Calcium go up and down throughout the day. Is this normal behavior? I only say this because I thought I had my reactor tuned in properly. I would test every day for a few days and it was always the same result. With a Trident however it is the same but I can see the ups and downs. I have attached my graphs as an example. I wanted to make sure something is not leaching into the tank or this is simply normal.

The drop and rise is significant. Alkalinity swing is about .2 DKH and calcium is about 15-20PPM.

 

[dz6t]

That may due to the testing methods inaccuracies.

 

[Derrick Picker]

So the trident is not accurate? But it appears to be the same each day and about the same numbers on the hour.

 

[Ranjib]

I would say it’s normal to see the cycle . We know ph and other parameters have daily cycle too. What I’m curious is to see the degree of fluctuation and how it impacts the coral health . From my primitive understanding I think your tank is super stable . If you don’t mind asking , what time your light comes up and what time light does off ?

 

[Derrick Picker]

I tend to agree with you. If I see the same alkalinity and calcium at each hour throughout the day I would assume that is stable am I wrong? That was my concern is if the reactor was tuned properly as it goes up and down but remains within the same range. My lights come on at around 10am and turn off around 5pm.

 

[dz6t]

Your system is stable enough, don’t worry about it.
The up and down are within the margins of error consider the testing methods.

 

[Derrick Picker]

Well I have a few corals struggling but overall things look very healthy. I just wanted to make sure that things are working properly. Also to the other mention I have posted what Randy said in a thread a while back.

 

[o2manyfish]

Your adding Calc and Alk 24/7 at a constant rate - But your corals are consuming at much greater rates when photosynthesizing. I was amazed to discover about 5 months how much this can actually be. I am using an Alkatronic. I have (2) 180g frag tanks outside in the sun - part of a 1300g sps system. The Alkatronic first showed how the consumption of the entire system was based on sunrise and sunset -- My 400g display tank - packed with SPS - has no visible effect when comparing to the consumption and replacement being driven by the frag tanks.

Then after the we hit the vernal equinox and we started having longer days - within a period of 2 weeks the alk consumption tripled!!!! More daytime hours - more time for the corals the consume. Currently if I shut my calcium reactor off during the day my alk drops .5 every hour.... Thats a .5 drop in 1300g of water.

They told us before the days of machine testing to test everyday at the same time - and this was so that with the cycle of corals consume all day and dosing or reactor replenishes all night you test during the same photo period to get the average daily dkh. But now we can see how the rates change.

Last year I took a screwdriver and hammer to break off a 6" by 18" rim of ORA Jedi Mind Trick. Just hammering at one coral in a 1300g system. But within hours the Alk shot up. I ticked off the corals and they stopped consuming alk. It was almost 5 days before the consumption went back to where it was.

These new tools are going to teach us alot more about what it really takes to maintain stability.

Dave B

 

[Derrick Picker]

Your adding Calc and Alk 24/7 at a constant rate - But your corals are consuming at much greater rates when photosynthesizing. I was amazed to discover about 5 months how much this can actually be. I am using an Alkatronic. I have (2) 180g frag tanks outside in the sun - part of a 1300g sps system. The Alkatronic first showed how the consumption of the entire system was based on sunrise and sunset -- My 400g display tank - packed with SPS - has no visible effect when comparing to the consumption and replacement being driven by the frag tanks.

Then after the we hit the vernal equinox and we started having longer days - within a period of 2 weeks the alk consumption tripled!!!! More daytime hours - more time for the corals the consume. Currently if I shut my calcium reactor off during the day my alk drops .5 every hour.... Thats a .5 drop in 1300g of water.

They told us before the days of machine testing to test everyday at the same time - and this was so that with the cycle of corals consume all day and dosing or reactor replenishes all night you test during the same photo period to get the average daily dkh. But now we can see how the rates change.

Last year I took a screwdriver and hammer to break off a 6" by 18" rim of ORA Jedi Mind Trick. Just hammering at one coral in a 1300g system. But within hours the Alk shot up. I ****** off the corals and they stopped consuming alk. It was almost 5 days before the consumption went back to where it was.

These new tools are going to teach us alot more about what it really takes to maintain stability.

Dave B

Thank you so much for this well written statement. I figured the same thing. I guess the main question really then is it imperative that we make it as stable as possible or will the amount of swing I have not really effect anything? If the swing is so severe and that indeed it effects coral growth and health then I would like to ask how can we rectify this. Make the calcium reactor only turn on during certain point of the day? Make the pH in the reactor different through different hours of the day?

 

[dz6t]

If what you see is due to coral calcification, how do you explain the up and down trends of calcium and alkalinity do not follow each other?

 

[Derrick Picker]

I agree with you on that also but isn't it true when calcium goes down alkalinity typically goes up and visa versa?

 

[dz6t]

When you over dose calcium or alk, one can suppress the other. This is not the case for you.
Coral take in calcium and carbonate (alk) at 1 to 1 ratio for calcification.

 

[Derrick Picker]

Hmm, so if that is the case then is something wrong with the Trident or the reactor tuning?

 

[dz6t]

Your reactor is fine and very stable. The Teident is doing its best also, that is as good as it can do.

 

[dz6t]

Calcium reactor puts out Calcium and alk at the same rate, so the trends you are seeing have nothing to do with the reactor.

 

[Derrick Picker]

Completely agree. That is why I was stumped by the Tridents results. I figure something is wrong with it honestly.

 

[dz6t]

I will consider it is pretty good already. The testing methods have their limitations.

 

[Snookin]

I really wouldn’t quantify a roughly .2 swing in ALK as “significant”. The chart looks like a big deviation but breakdown the data. Don’t just look at it visually without using your brain to analyze what it is saying. A less than .2 swing in a 24hr period is stable.

 

[o2manyfish]

To throw another wrench into the issue - You also have to 'learn' about the type of alkalinity being measured. I was just schooled on this the past week. Titration methods meausre 'Total Alkalinity" - which is comprised of Carbonate Alkalinity and Borate Alkalinity. Corals due not consume both of these types of alkalinity at the same rate. The Borate Alkalinity is a 'value' that is different for different aquarium system. So during the day what's really going up and down is the Carbonate at a much greater rate than Borate. But most of the testing methods only measure Total Alk. Some aquariums the Borate Alkalinity can be under 5% of the total. And in other systems it could be 40%+. If you have one of the aquariums where the Borate is 40%. Then you could see stable Alk readings, when in fact your true Carbonate is changing more than you would like.

And you could also think you are on target with a dkh of "8.5" - But in fact the carbonate alkalinity of your system could be way below what you really want to target. And your non-connected frag tank with a dkh of 8.5 has a much lower Borate Alkalinity level which means the Carbonate Alkalinity is much higher ie closer to the 8.5 you want.

Doesn't that make things more confusing

Dave B

 

[Derrick Picker]

I really wouldn’t quantify a roughly .2 swing in ALK as “significant”. The chart looks like a big deviation but breakdown the data. Don’t just look at it visually without using your brain to analyze what it is saying. A less than .2 swing in a 24hr period is stable.

Yes but is +/- 30 PPM of calcium normal? Somedays it is not even close.