Two part versus Calcium Reactor thoughts...

[Reef55]

I used b-ionic years ago.. then "upgraded" to a calcium reactor. About 5 months ago I switched back to a two part additive (soda ash and calcium chloride).

When I switched, I stopped all alk / calcium / magnesium additives for 7 days. I measured on day 1, 4, and 7 my levels (3 measurements of each parameter each time, and averaged the results.) The results were consistent in that I used the same amount of calcium / alk / magnesium per day.

With two-part solutions, I know the exact concentration of calc / alk. I also know my water volume, and how much I am consuming. Simple math from there tells me how much of each two part solution I need to add every day to replace what my tank consumes. I have it dosed by a peristalic pump. So in my setup, I know for certain exactly how much alk and calcium is being added every day to my system. In the last four months, I only needed to change (increase, as I added a few new corals), my dosing amount. Since I know how much I add per day, I can calculate how much to change the dosing amount by to keep up with demand. When I need to make up more, I know that the amount I am adding will be identical to the last time it was set up. Additionally, changes to the amount dosed are instant. Last, the only thing I need to change is the amount dosed per day.

The potential causes of errors to my method:

1) Incorrectly mixed solution (I measure the additives by weight)
2) Solutions run out (in clear bottles, easy to see if I am running low)
3) Change in alk / calcium demand of system (add / remove corals, growth, lighting change, etc)



Now take the calcium reactor setup... there is no way to know how much alk / calcium you are adding per day. To know if a change to a reactor is the right change takes days to determine. And for me, the biggest problem with a calcium reactor are that too many things can change, so even if you have it dialed in perfect today, 3 days from now it is off again.

The potential causes of errors to a calcium reactor:

1) Bubble count drift (needle valve shifts, CO2 tank is running low (but not out yet))
2) Effluent rate drift (input pressure changed, lines clogged, less backpressure as media dissolves)
3) Internal chamber pH drift (effected by both of the above changes, which changes the amount of media dissolved and hence how much alk / calcium is added)
4) Media amount changes (constantly getting lower, which means the amount being dissolved may or may not change depending on the efficiency of the reactor to consume all the CO2)
5) CO2 runs out (hard to see)
6) Media runs out (easy to see)
7) Setting up again (near impossible to have the same bubble count, effluent rate, media amount, etc as a previous time, so go through the whole setting process each time you clean the reactor, refill the CO2, add more media, etc)
8) Change in alk / calcium demand of system (add / remove corals, growth, lighting change, etc)


I tried a calcium reactor for years... and felt like bashing my head against a wall all the time due to the above fluctuations. Maybe I just wasn't good at dialing in my reactor, but every time I checked my levels, something would be off that I would have to correct for (add something, or turn off the reactor and then add something then turn back on the reactor, etc).

So I sold my calcium reactor setup, bought a good dosing pump, bought enough food grade two part additives to last me around 2 years, and still had money left over. My only regret is not doing this years ago!


For those that are interested, here is an excel calculator I wrote for determing how many minutes per day a dosing pumps needs to be on for:

http://www.mspreef.com/files/additives.xls

 

[pvh]

Looks good Mark.
The more components you have in the system the more changes for errors. That's why I manually dose my tank.

 

[Dave McReeferson]

Looks good Mark.
The more components you have in the system the more changes for errors. That's why I manually dose my tank.

I have been running a system much like what Mark describes here for some time now (nearly two years) with very good luck. To keep the risk of equipment failures from reaking havoc on our system, I used peri-pumps chosen for flow rates such that if left on 24 hours a day, they fall just a hair shy of making up for my average daily evaporation. The intakes of these pumps draw from barrels that contain Kh and Ca supplements. Rather than relying on timers to adjust the amount pumped per day, I vary the concentration of these solutions to match demand. It is an easy as pie and nearly fool proof system, save for a careless mixing mistake by me, it is virtually impossible to overdose.

 

[Liam]

my thoughts are,simple math is not always so simple
http://www.bostonreefers.org/forums/showthread.php?t=56586
sorry mark could'nt resist,neither method is 100%

What i will say though is that i am far happier dissolving coral skeletons that originated from the reef than dosing various icemelt products that contain many unatural susbstances and i see that as a dissadvantage that should be on the list.

 

[delta]

Two part versus Calcium Reactor thoughts...

I would compare running out of CO2 as easy to see as running out of Dosing solutions. I think you make some good points but I also think you over simplified dosing and over complicated the Calcium reactor setup.

You just never got it down that is all, I would also worry about dosing too much at a certain point, how many ml/per gal is safe to dose a tank?

Not sure why you had so much trouble, but I change media, CO2 tanks, water changes etc and never have to reset everything again. I do monitor it but my reactor is dialed in correctly and even with all the chanes everygthing stays in line. Perhaps you run an unbalanced system? Calc, Alk, Mag?

I am not saying one is right over the other, I just think it is a very bias statement. As I am sure more people have trouble balancing parameters with dosing than a reactor. I have done both and both have pretty much the same pitfalls with tank related changes.

 

[chew*]

I do neither, I kalk it up and as Dave said instead of changing the quantity I drip I change the amount of kalk added to solution.

 

[Greg Hiller]

Mark, you certainly make a lot of good points. One thing though:

>Now take the calcium reactor setup... there is no way to know how much
alk / calcium you are adding per day.<

That's not actually true. It's really not hard to measure the alk or calcium level (and they should always be close to a fixed ratio) coming out of a reactor. It's also easy measuring the flowrate of liquid coming out, so the actual calcium and alk added via a reactor is not hard to measure.

One reason (not saying this is enough to justify a reactor) some people like reactors is that as they are dissolving substrate they are oftentimes using a coral based substrate, so everything (within reason) that a coral needs should be being added by the reactor.

My own experience with reactors has been that they are usually pretty forgiving of the way they are operated. Sometimes people (not saying this is you Mark ) get a little over concerned about the exact pH of the reactor, the effluent rate, etc., etc., and can become irritated if they cannot control it perfectly. I generally eye-ball the rates a just about all my reactors and just check the alkalinity frequently. Also, while many of the problems you listed for reactor certainly do occur, there are also many ways around the problems that I've learned over the years.

All of this also needs to be taken in a historical perspective as well. Prior to the availablility of inexpensive two-part solutions, in the long term it was a lot less expensive to set up a reactor (particularly if it was a homemade reactor). So, people naturally went to reactors as their tanks got bigger or had more fast-growing corals.

One aspect of the two-part solutions that I worry about is that at the really high use rates, I wonder about the other elements that are being added, but not necessarily consumed by the corals. Also, with the changes in bromide levels in Dowflake, I don't know whether they days of cheap two-part solutions are coming to an end.

 

[Reef55]

I would compare running out of CO2 as easy to see as running out of Dosing solutions. I think you make some good points but I also think you over simplified dosing and over complicated the Calcium reactor setup. .

I wrote that problem in both groups.

What did I leave out for dosing? What did I add that I should not have for the calcium reactor setup?

You just never got it down that is all, I would also worry about dosing too much at a certain point, how many ml/per gal is safe to dose a tank?

how many ml/per gal is safe to dose with a calcium reactor?

Not sure why you had so much trouble, but I change media, CO2 tanks, water changes etc and never have to reset everything again. I do monitor it but my reactor is dialed in correctly and even with all the chanes everygthing stays in line. Perhaps you run an unbalanced system? Calc, Alk, Mag?

Alk / calcium / mag are 8.0dkh / 400 ppm / 1300 ppm. When I did my measurements, I consumed 19.97 ppm of calcium for each meq/l of alk, which is pretty darn close to the 20:1 ratio it should be according to Randy. So I don't think I fall in the unbalanced category.

Maybe it was just my reactor, but I had to close the needle valve on my CO2 to refill the CO2 or to clean the reactor. That meant resetting that each time, which counting bubbles for a minute is just not an accurate process to me.

I am not saying one is right over the other, I just think it is a very bias statement. As I am sure more people have trouble balancing parameters with dosing than a reactor. I have done both and both have pretty much the same pitfalls with tank related changes.

I am not saying 2 part is the best solution and everyone should use it either, I just merely expressed my experiences with both and what I have chosen to do. You figured out exactly how much 2 part to dose with an accurate metering pump before? Or you just dosed 2 part?

 

[Reef55]

my thoughts are,simple math is not always so simple
http://www.bostonreefers.org/forums/showthread.php?t=56586
sorry mark could'nt resist,neither method is 100%

Ahh figured that would come up... that is not a math nor method error, that is me being stupid error The method was not to blame, my programming my AC3 at 1AM was the problem.

What i will say though is that i am far happier dissolving coral skeletons that originated from the reef than dosing various icemelt products that contain many unatural susbstances and i see that as a dissadvantage that should be on the list.

Ok, I understand the dissolving coral skeletons part being a good thing, however, using food-grade calcium chloride and food grade baked soda ash are not the same thing as "various icemelt product that contain many unnatural substances". Did you pick your coral skeletons up from a dead coral reef yourself? No? Then you don't know what crap is in your reactor either my friend

Oh, and I bet you don't really know what are in all those zeovit bottles you religiously drip into your tank each day either

 

[Greg Hiller]

>Maybe it was just my reactor, but I had to close the needle valve on my CO2 to refill the CO2 or to clean the reactor. That meant resetting that each time, which counting bubbles for a minute is just not an accurate process to me<

Unless I'm specifically adjusting the flowrates I never touch the needle valves. When I change tanks I just close the big valve. Spin the regulator off the old and onto the new bottle quickly. Open the big valve again and usually everything goes back to the same spot it was in. I've learned over the years to know when the CO2 was about to run out becuase the flow is a bit faster and I usually see a bit more algae on the glass. Over the past 8 years running I've probably changed tanks 30+ times and only run completely out 2-3 times (once because of a leak).

 

[Reef55]

Mark, you certainly make a lot of good points. One thing though:

>Now take the calcium reactor setup... there is no way to know how much
alk / calcium you are adding per day.<

That's not actually true. It's really not hard to measure the alk or calcium level (and they should always be close to a fixed ratio) coming out of a reactor. It's also easy measuring the flowrate of liquid coming out, so the actual calcium and alk added via a reactor is not hard to measure.

You are correct Greg in that it is possible to measure the amount of calcium / alk coming out of a reactor. However, it does need to be diluted out for the standard hobby test kit (diluting = potential source of measurement error) to get a reading. Also, my concern is that the amount doesn't stay constant from what it was measured at. As the flowrate and / or bubble count shifts, or the amount of media reduces, the amount being added changes.


Again, I never said that there are not merits to a calcium reactor. Just trying to show that a bigger expensive toy is not always the better option

 

[Greg Hiller]

>Did you pick your coral skeletons up from a dead coral reef yourself?<

You've got a point there also, but there have been some elemental analyses done on calcium reactor substrates. I did some myself, but I'm not sure the data still exists on the web. Okay...I just looked. Some of the old articles have been 'refreshed' and still exist:

http://www.fishchannel.com/saltwate...aquarium-frontiers/calcium-reactor-substrates

 

[Greg Hiller]

>You are correct Greg in that it is possible to measure the amount of calcium / alk coming out of a reactor. However, it does need to be diluted out for the standard hobby test kit (diluting = potential source of measurement error) to get a reading. <

I suppose there could be some minor error in dilution, but if you know what you are doing it's not really going to significantly effect the numbers. Using the alk testing method the club uses there is no requirement to dilute.

>Also, my concern is that the amount doesn't stay constant from what it was measured at. As the flowrate and / or bubble count shifts, or the amount of media reduces, the amount being added changes.<

Agreed, no question there. OTOH, if you have a MONSTER reactor, things don't change quite as fast.

>Again, I never said that there are not merits to a calcium reactor. Just trying to show that a bigger expensive toy is not always the better option<

No arguement there.

 

[delta]

Dosing description
2) Solutions run out (in clear bottles, easy to see if I am running low)
Calcium reactor description
5) CO2 runs out (hard to see)

With a pressure gauge and bubble counter you have a really good idea of how much CO2 you have left. The description make it seem as is hard to
see when you are out of CO2. Not a big issue on something you change out one every six month to a year. I doubt you refill your dosing bottles bi anually?

Also I am not sure why you had to close your needle valve to remove the CO2
Bottle? I think your problem was probably your regulator, which if it were not good quality or in good shape would drive anyone nuts.

Again, I never said that there are not merits to a calcium reactor. Just trying to show that a bigger expensive toy is not always the better option

I spent about 400 to get my reactor up and running. In looking at setting up a dosing system it would have cost me that easy.

 

[Reef55]

>Did you pick your coral skeletons up from a dead coral reef yourself?<

You've got a point there also, but there have been some elemental analyses done on calcium reactor substrates. I did some myself, but I'm not sure the data still exists on the web. Okay...I just looked. Some of the old articles have been 'refreshed' and still exist:

http://www.fishchannel.com/saltwate...aquarium-frontiers/calcium-reactor-substrates

Just like with the dow chemicals increasing their bromide, do you know for sure whether or not the crushed coral of Nature's Ocean brand, Atlantic crushed coral, #4 World Wide Imports, Inc that you tested is still from the exact same place? And although you tested for a lot a of different things, we are all aware I think that we don't know what every level should be, nor if something should have been tested that wasn't.

Liam, I am sure you use something to adjust your calcium / alk / mag levels outside of your reactor, even if it is just in your water changes. Do you know what you are adding then is perfectly pure?

Bottom line is we add a lot of things to our tanks (water, food, chemicals, airborne contaniments, etc), and don't truly know what is in any of them really. I personally don't see food-grade calcium and alkalinity supplements as something to be worried about.

 

[Reef55]

I spent about 400 to get my reactor up and running. In looking at setting up a dosing system it would have cost me that easy.

Cole-palmer dual headed doser from someone on this forum: $90
Enough 2 part to last 2 years: $100

$190 spent with $210 to waste (err, I mean spend) on corals

 

[delta]

Cole-palmer dual headed doser from someone on this forum: $90
Enough 2 part to last 2 years: $100

$190 spent with $210 to waste (err, I mean spend) on corals

What about the AC3?

 

[Randy Holmes-Farley]

Well, I do not pick either of these two methods as I choose to use limewater, but I'll make a few observations. Starting with the fact that both obviously work perfectly well when used properly, but may each have their own idiosyncrasies that folks might want to be aware of.

The various analyses of commercial reactor substrates by Greg and others that I have seen do not match fresh coral skeleton data in the scientific literature. Whether that is good, bad or otherwise, one cannot simply assume that you are adding what corals are taking out. Strontium, for example, is quite deficient in some commercial products relative to fresh coral skeletons. I discuss that with data here:

Strontium and the Reef Aquarium
http://www.advancedaquarist.com/issues/nov2003/chem.htm

And to some extent that hypothesis assumes that what corals deposit is what they need, which clearly is not the case for many impurities including those for which there is no biological function.

Finally each coral species deposits a different assembly of ions. Coralline algae, for example, takes out a lot more magnesium that do many SPS corals. So it is not the case the coral skeletons will keep the tank stable unless they exactly match what is growing in the tank. I show the magnesium amounts in various organisms here:

Magnesium in Reef Aquaria
http://www.advancedaquarist.com/issues/oct2003/chem.htm

 

[Liam]

but even though the acIII was the problem its all part of the equation with dosing.

ok ok you got me
but we are not disscusing zeovit method here ,we are discussing the pro's and cons of calcium/alk dosing

I did not mean to come across as one being better than the other i was just expressing one of the reasons i feel it is worth using a reactor over dosing.

apart from yourself i expect most ARE using dowflake etc.

 

[Liam]

Well, I do not pick either of these two methods as I choose to use limewater, but I'll make a few observations. Starting with the fact that both obviously work perfectly well when used properly, but may each have their own idiosyncrasies that folks might want to be aware of.

The various analyses of commercial reactor substrates by Greg and others that I have seen do not match fresh coral skeleton data in the scientific literature. Whether that is good, bad or otherwise, one cannot simply assume that you are adding what corals are taking out. Strontium, for example, is quite deficient in some commercial products relative to fresh coral skeletons. I discuss that with data here:

Strontium and the Reef Aquarium
http://www.advancedaquarist.com/issues/nov2003/chem.htm

And to some extent that hypothesis assumes that what corals deposit is what they need, which clearly is not the case for many impurities including those for which there is no biological function.

Finally each coral species deposits a different assembly of ions. Coralline algae, for example, takes out a lot more magnesium that do many SPS corals. So it is not the case the coral skeletons will keep the tank stable unless they exactly match what is growing in the tank. I show the magnesium amounts in various organisms here:

Magnesium in Reef Aquaria
http://www.advancedaquarist.com/issues/oct2003/chem.htm

two part dosing does not deliver strontium either though.

I prefer to use the schuran type media that is easily identified as pieces of coral skeleton rather than media's such as ARM etc that could be ground up anything,as mentioned.